Water 72·1 72·0 69·0
Cellulose 9·9 9·8 10·0
Salts —— 0·4 0·7-1·2
The cane, therefore, may be said to yield 90 per cent. of juice, which
latter contains from 18 to 20 parts of pure sugar. However, the actual
quantity obtained is rarely if ever more than 1 lb. of sugar to a gallon
of juice, or 10 per cent.; and much more frequently only 8 per cent.
A large part of this loss is due to the prolonged exposure of the cane
juice during its repeated boilings to heat, whereby a large proportion of
its crystallisable sugar is converted into the uncrystallisable variety
which passes away in the form of molasses and treacle. Another important
cause of loss is the retention of a large amount of juice by the cane.
The following figures will convey an idea of the enormous quantities of
cane sugar produced and consumed yearly throughout the globe. It is taken
from ‘British Manufacturing Industries,’ one of a series of excellent
industrial manuals published by Mr Sandford, of Charing Cross:——
Cuba 600,000 tons.
The other West Indian colonies 250,000 ”
Java and Sumatra 170,000 ”
China 140,000 ”
French colonies in America and Africa 120,000 ”
Brazil 100,000 ”
Mauritius 80,000 ”
British Guiana 80,000 ”
Porto Rico 90,000 ”
Manilla 60,000 ”
Mexico 35,000 ”
Egypt Large and growing.
The late Dr Edward Smith found that 98 per cent. of indoor operatives
partook of 7-1/2 oz. of sugar per adult weekly; that 96 per cent. of
Scotch labourers use it; and 80 per cent. of Irish. He further states that
in Wales sugar is commonly used to an average extent of 6 oz. per adult
weekly; but that there is a marked difference in the rate of consumption
in the northern and southern portions of the principality. In North Wales,
for example, the average amount per head is 11-1/4 oz.; whereas in South
Wales it is only 3 oz.
The manufacture of sugar is exclusively conducted on the large scale. The
recent canes are crushed between rollers, and the expressed juice is
suffered to flow into a suitable vessel, where it is slowly heated to
nearly the boiling-point, to coagulate albuminous matter. The crushed
canes generally supply the fuel needed for this purpose. The ashes left
after the combustion of the canes are carefully collected and used as a
manure for future crops of sugar cane.
The cut below represents a press for the extraction of the juice from the
canes. By means of the screws (_i i_), the rollers are adjusted to the
proper distance apart; the upper roller is half the size of the two lower
ones, and all are moved by cogged wheels fitting on to the axes of the
rollers. The sugar-canes are transferred from the slate gutter (_d d_) to
the rollers (_a c_), which press them a little; and from thence they are
carried over the arched plate (_n_) to the rollers (_c b_). The pressed
sugar-canes fall over the gutter (_f_), the expressed juice collecting in
_g g_, and running off through _h_. A small quantity of milk of lime is
then added to the juice to remove mechanical impurities, and the skimmed
and clarified juice, after being sufficiently concentrated by rapid
evaporation in open pans, is transferred to coolers, and thence into
upright casks perforated at the bottom, and so placed that the syrup, or
uncrystallisable portion, may drain off into a tank or cistern from the
newly formed sugar. During the period of crystallisation it is frequently
agitated, in order to hasten the change, and to prevent the formation of
large crystals. The solid portion of the product forms moist, raw, or
muscovado sugar; the uncrystallisable syrup, molasses or treacle.[202]
[Footnote 202: The term ‘molasses’ is usually restricted to the drainings
from raw sugar, and ‘treacle’ to the thicker syrup which has drained from
refined sugar in the moulds.]
[Illustration]
Raw sugar is refined by redissolving it in water, adding to the solution
albumen, under the form of serum of blood or white of egg, and, sometimes,
a little lime-water, and heating the whole to the boiling-point; the
impurities are then removed by careful skimming, and the syrup is
decoloured by filtration through recently burnt animal charcoal; the clear
decolorised syrup is next evaporated to the crystallising-point in vacuo,
and at once transferred into conical earthern moulds, where it solidifies,
after some time, to a confusedly crystallised mass; this, when drained,
washed with a little clean syrup, and dried in a stove, constitutes
ordinary loaf, lump, or refined sugar. Sometimes in washing the
crystallised mass for the purpose of removing the coloured syrup which is
mingled with it, the process known as ‘claying’ is followed.
In this case, instead of white syrup being used, a layer of thin mud or a
paste of thin pipe-clay is poured into the mould on to the base of the
inverted sugar cone, through which the water escaping from the mud or
pipe-clay permeates, and carries with it the coloured syrup. Neither the
mud nor the pipe-clay mix with the sugar, but remaining on the top soon
become hard, when they are removed. As the syrup running from the moulds
still contains a large quantity of crystalline cane sugar, this is
recovered as follows:
The syrup, after being sufficiently concentrated by boiling in the vacuum
pan, is removed and allowed to cool, when it assumes the appearance of a
crystalline magma known as ‘crushed sugar.’
Crushed sugar is a mixture of a large quantity of sugar crystals with
uncrystallisable syrup. To get rid of this latter from the crystals, the
mass is placed in quantities of 3 or 4 cwts. at a time in a ‘centrifugal
machine.’ This, of which an engraving is given below, consists, as will be
seen, of a drum fixed on a vertical axis. The walls of the drum are made
of perforated metal, or are formed of meshed wire work, and the drum
itself enclosed in an outer metal cylinder, which is fixed, and, of
course, unperforated. When the drum is made to revolve on its axis at the
rate of 1000 or 1200 revolutions in a minute, the syrup flying off by
centrifugal action, and escaping through the perforation at the sides of
the drum, is received into the outer cylinder, whence it escapes by a
trough into a proper receptacle, leaving behind the crystals in the
interior of the drum.
[Illustration]
_a_ is an open drum of fine meshed wirework, caused to revolve in the
cast-iron vessel (_b b_), by means of the bevel wheels (_c d_), gearing
with a motive power. The motion of the drum can be stopped by means of the
brake (_e_), and regulated by the weights placed at _o_.
When the crystallisation of sugar is allowed to take place quietly and
slowly, the product is sugar candy. The evaporation at a low temperature
in vacuum pans has the effect of diminishing the yield of treacle.
_Prop._ Sugar requires for its solution only 1/3rd of its weight of cold
and still less of boiling water; it is slowly dissolved by cold rectified
spirit; it dissolves in 4 parts of boiling rectified spirit and in 80
parts of boiling absolute alcohol; it melts by heat, and cools to a glassy
amorphous mass (barley sugar); at about 400° Fahr. it suffers rapid
decomposition, and fuses to a brown, uncrystallisable mass (caramel);
long boiling with water increases its colour, and lessens its tendency to
crystallise; its aqueous solution dissolves alkalies, earths, and many
metallic oxides, with facility. The presence of cane sugar in solutions
containing certain metallic salts prevents the precipitation of their
oxides by alkalies. The oxides of copper and iron are amongst those thus
kept in solution. Sugar also possesses the power of effecting the partial
or complete reduction of many metallic oxides, if boiled with their salts;
the first results is exemplified in the case of the chromates; for if a
chromate be added to a solution of sugar, and to the mixture a few drops
of free acid, the chromic acid suffers reduction to chromic oxide, which,
dissolving in the excess of acid, imparts a green colour to the liquid.
Mercuric salts become reduced to mercurous, whilst the salts of gold throw
down a precipitate of the metal in fine powder. The action of strong oil
of vitriol on cane sugar is very energetic. The sugar is instantly reduced
to a black charred mass, whilst carbonic and formic acids are given off.
The same effects are produced by exposing it to dry chlorine at a
temperature of 212° F. By nitric acid of sp. gr. 1·25, cane sugar is
converted into saccharic acid; if a stronger acid be employed, oxalic acid
is produced. When a mixture of concentrated nitric and sulphuric acids is
poured on to cane sugar, an explosive compound, resembling gun cotton, is
produced. This body is known as ‘nitro-sugar.’ Weak syrups take up about
half as much hydrate of calcium as they contain sugar; when slowly
crystallised, it assumes the form of oblique 4-sided prisms, terminated by
2-sided summits. Sp. gr. 1·60 (1·577——Ure).
_Pur._ Moist or muscovado sugar and crushed lump sugar are occasionally
adulterated with chalk, plaster, sand, potato-flour, and other fecula; but
frequently, and in certain neighbourhoods constantly, with starch sugar or
potato-sugar.[203] These frauds may be detected as follows:
[Footnote 203: See further on.]
_Tests._——1. Pure cane sugar dissolves freely and entirely in both water
and proof spirit, forming transparent colourless solutions, which are
unaffected by either sulphuretted hydrogen or dilute sulphuric acid.——2.
Its solution bends the luminous rays in circumpolarisation to the right,
whereas grape and fecula sugars bend it to the left.[204]——3.
(Chevallier.) Boiled for a short time in water containing 2 or 3% of
caustic potassa, the liquid remains colourless; but it turns brown, which
is more or less intense, according to the quantity, if starch sugar is
present. Even 2 or 3% of starch sugar may be thus detected.——4. (E.
Krantz.) A filtered solution of 33 gr. of cane or beet sugar in 1 fl. oz.
of water, mixed with 3 gr. of pure hydrate of potassium, and then agitated
with 1-1/2 gr. of sulphate of copper in an air-tight bottle, remains
clear, even after the lapse of several days; but if starch sugar be
present, a red precipitate is formed after some time; and if it is present
in considerable quantity, the copper will be wholly converted into oxide
within 24 hours, the solution turning first blue or green, and then
entirely losing its colour.——5. (Trommer’s test.) A solution of cane sugar
is mixed with a solution of sulphate of copper, and hydrate of potassium
added in excess; a blue liquid is obtained, which, on being heated, is at
first but little altered; a small quantity of red powder falls after a
time, but the liquid long retains its blue tint. When grape sugar or
fecula sugar is thus treated, the first application of heat throws down a
copious greenish precipitate, which rapidly changes to scarlet, and
eventually to dark red, leaving a nearly colourless solution. This is an
excellent test for distinguishing the two varieties of sugar, or
discovering an admixture of grape sugar with cane sugar. The 1/1000th part
of grape sugar may be thus detected. The proportion of oxide of copper
produced affords a good criterion, not only of the purity of the sugar,
but also of the extent of the adulteration.——6. (Ure.) Dissolve a little
sulphate of copper (say 20 gr.) in a measured quantity of water, and add
to it, in the cold, a solution of hydrate of potassium, until, by testing
with turmeric paper, the liquid appears faintly alkaline, shown by the
paper becoming slightly brown. If a small quantity of this test-liquor
(previously well shaken) be added to an aqueous solution of the sugar, and
the whole boiled, the solution becomes at first green, and then
olive-green, if dextrin is present; but if it contain grape sugar, the
salt of copper is immediately reduced into the state of orange and oxide;
whilst a solution of pure sugar undergoes no change, or is scarcely
altered.——7. M. Riffard,[205] taking advantage of the fact that sugar,
like tartaric, malic, citric acid, and albumen, prevents the precipitation
of iron by ammonia, employs iron as a means for estimating sugar. A
solution containing sugar and iron in a certain proportion, when saturated
with ammonia, will form a compound of a fine red colour, which remains
clear if no alkaline earthy metals are present. M. Riffard has applied to
sugar the method proposed by M. Juette for the estimation of tartaric
acid. He observed that a neutral or acid solution of crystallised
perchloride of iron, when heated for a considerable time to 100° C,
requires 2·710 grams of sugar, if 100 milligrams of iron are to remain in
solution in the presence of ammonia. If, on the other hand, the solution
is prepared simply by dissolving crystallised perchloride of iron in pure
water, without the addition of an acid, 100 milligrams of iron only
require 2·587 grammes of sugar to remain dissolved. In this case the
liquid is perfectly clear, and remains so; but if a smaller quantity of
sugar be added, it is turbid, and deposits peroxide of iron. To estimate
the sugar by this process, 25·870 grammes of the substance to be tested
are dissolved, the solution mixed with a few drops of oxalate of ammonia
to precipitate the lime, filtered and made up with water to 250 c.c., 25
c.c. of this mixture require the addition of as many milligrams of iron
as there are per cents. of pure sugar in the sample under examination, and
by two tests the following results will be arrived at:——With _n_
milligrams of iron the solution is clear. With _n_ + 1 milligrams of iron
the solution is precipitated. _n_ representing the number of per cents. of
sugar contained in the sample.——8. M. Perrot’s method for the
determination of sugars by means of normal solutions is as follows:——He
prepares a standard solution of copper by dissolving 39·275 grams of
sulphate of copper, very pure, and dried between several folds of
filtering paper, and makes it up with distilled water to 1000 c.c. Each
c.c. of this solution contains 0·01 grams of copper. On the other hand,
he dissolves about 25· grams of pure cyanide of potassium in 1 litre of
distilled water. Of this solution 10 c.c. are taken and put in a flask,
to which about 20 c.c. of ammonia are added, and the liquid is kept at a
temperature of 60° or 70°. He pours in the copper solution drop by drop by
means of a burette graduated into tenths of a c.c., until there appears
the blue tint characteristic of salts of copper in an ammoniacal solution.
The number of degrees of the burette are then read off, and indicate the
quantity of copper which has been required to produce the reaction. The
solution of the sugar in question (previously inverted if it is required
to determine crystalline sugar) is then placed in contact with an excess
of Fehling’s liquor, and reduced in the water-bath. The whole is filtered
in order to collect the precipitate of suboxide, which is first well
washed with hot water, and dissolved in nitric acid, diluted with an equal
volume of water, and a few fragments of chlorate of potassa are added.
This solution is effected on the filter, which is then carefully washed in
acidulated water. The filtrate to which the washings are added is then
mixed with water enough to make up 100 or 150 c.c., and is then poured by
means of the burette into 10 c.c. of cyanide, mixed with 20 c.c. of
ammonia as above, stopping when the blue colour appears, and reading off
the quantity of copper employed. From the former experiment it is known
how much copper 10 c.c. of the cyanide solution require. Hence it is easy
to calculate the total amount of copper which has been present as
suboxide. The amount of sugar is then found from the data that 9298 parts
of copper equal 5000 of crystalline sugar, or 5263 of glucose.[206]——9.
The specific gravities and crystalline forms offer other means of
distinguishing the varieties of sugar.
[Footnote 204: Of late years, owing to the little difference in price
between the two, this form of adulteration has been abandoned.——ED.]
[Footnote 205: ‘Journ. de Pharm. et de Chimie,’ 1874, 49 (‘Pharm. Year
Book,’ 1874).]
[Footnote 206: ‘Comptes Rendus Hebdomadaire des Sciences’ (‘Chem. News’),
January 5th, 1877.]
_Concluding Remarks._ Refined sugar (SACCHARUM——Ph. L., S. PURUM——Ph. E.,
S. PURIFICATUM——Ph. D.), raw sugar (S. COMMUNE——Ph. E.), and molasses or
treacle (SACCHARI FÆX——Ph. L. & E.), were officinal.
The relative sweetening power of cane sugar is estimated at 100; that of
pure grape sugar, at 60; that of fecula or starch sugar, at 30 to 40.
According to Messrs Oxland’s method (patented 1849) of defecating and
bleaching the juice of beet-root, cane, &c., acetate of aluminium, formed
by dissolving 4 lbs. of that earth in acetic acid, is boiled with each ton
of sugar, and as soon as the acetic acid is nearly all driven off, a
solution of tannin, formed from 1 lb. of bruised valonia and 2 galls. of
hot water, is added to the boiling syrup; the excess of aluminium is
afterwards separated by lime, and the usual method of further procedure
adopted. By their second patent (1851), superphosphate of aluminium or of
calcium is substituted for acetate of aluminium, in the proportion of
about 6 lbs. of aluminium, dissolved in phosphoric acid, for each ton of
sugar.
The presence of certain saline bodies in a solution of cane sugar,
exercises a very prejudicial effect upon it, since these, by combining
with the sugar, give rise to compounds which contribute to the more or
less reduction of the sugar to the uncrystallisable condition, and to a
consequent increase of the molasses.
Of one of the chief constituents of the sugar-cane that possesses this
objectionable property is potash in combination with acids, both organic
and inorganic. Last year a patent for the removal of these potash salts
was taken out by the Messrs Newlands. The patentees proceed upon the facts
that the solubility of alum in water is very trifling, and that it
contains only 1/10th part of its weight of potash. They add to a
concentrated syrup a strong solution of sulphate of alumina (having by a
previous examination of the syrup determined the quantity required).
Sulphate of potash is thereby formed, and this, uniting with the sulphate
of alumina, the resulting alum after a time deposits in a crystalline form
at the bottom of the vessel containing the sugar solution. This being run
off into another receptacle, the free acid, of which it now contains a
large quantity, is neutralised with lime or chalk, boiled, filtered, and
passed through charcoal.
The addition of the lime has also thrown down the alumina liberated by the
reaction, which has carried with it and removed certain injurious
nitrogenous principles previously present in the saccharine liquid.
Some few years back Messrs Dubrunfaut and Péligot being cognisant of the
fact of the insolubility, in boiling water, of the compounds of sugar with
lime, based upon it a method of separating crystallisable sugar from
treacle. Péligot has obtained from common treacle one fourth of its weight
of crystallised sugar, by dissolving the precipitated sugar lime in water,
and separating the lime by passing into the mixture a stream of carbonic
acid.
Sugar may be obtained from nearly all sweet vegetable substances, by a
process essentially similar to that described above.
_Table showing the Specific Weight of Sugar Solutions
with the corresponding percentage of Cane Sugar at
17·5° C._——GERLACH.
------------------------+-------------------------+----------------------
Percentage, Specific |Percentage, Specific |Percentage, Specific
Cane Sugar. Weight |Cane Sugar. Weight |Cane Sugar. Weight
of Sol. | of Sol. | of Sol.
| |
75 1·383,342 | 49 1·227,241 | 24 1·101,377
74 1·376,822 | 48 1·221,771 | 23 1·096,792
73 1·370,345 | 47 1·216,339 | 22 1·092,240
72 1·363,910 | 46 1·210,945 | 21 1·087,721
71 1·357,518 | 45 1·205,589 | 20 1·083,234
70 1·351,168 | 44 1·200,269 | 19 1·078,779
69 1·344,860 | 43 1·194,986 | 18 1·074,356
68 1·338,594 | 42 1·189,740 | 17 1·069,965
67 1·332,370 | 41 1·184,531 | 16 1·065,606
66 1·326,188 | 40 1·179,358 | 15 1·061,278
65 1·320,046 | 39 1·174,221 | 14 1·056,982
64 1·313,946 | 38 1·169,121 | 13 1·052,716
63 1·307,887 | 37 1·164,056 | 12 1·048,482
62 1·301,868 | 36 1·159,026 | 11 1·044,278
61 1·295,890 | 35 1·154,032 | 10 1·040,104
60 1·289,952 | 34 1·149,073 | 9 1·035,961
59 1·284,054 | 33 1·144,150 | 8 1·031,848
58 1·278,197 | 32 1·139,261 | 7 1·027,764
57 1·272,379 | 31 1·134,406 | 6 1·023,710
56 1·266,600 | 30 1·129,586 | 5 1·019,686
55 1·260,861 | 29 1·124,800 | 4 1·015,691
54 1·255,161 | 28 1·120,048 | 3 1·011,725
53 1·249,500 | 27 1·115,330 | 2 1·007,788
52 1·243,877 | 26 1·110,646 | 1 1·003,880
51 1·238,293 | 25 1·105,995 | 0 1·000,000
50 1·232,748 | |
------------------------+-------------------------+----------------------
=Sugar, Al′um.= _Syn._ SACCHARUM ALUMINATUM, ALUMEN SACCHARINUM, L. From
alum and white sugar, in fine powder, equal parts, formed into minute
sugar-loaf shaped lumps with mucilage of gum Arabic made with rose water.
Used to make astringent lotions and eye-waters.
=Sugar. Bar′ley.= _Syn._ SACCHARUM HORDEATUM, PENIDIUM, SACCHARUM
PENIDIUM, L. _Prep._ Take of saffron, 12 gr.; hot water, q. s.; sugar, 1
lb.; boil to a full ‘candy height,’ or that state called ‘crack,’ or
‘crackled sugar,’ when 2 or 3 drops of clear lemon juice or white vinegar
must be added, and the pan removed from the fire and set for a single
minute in cold water, to prevent its burning; the sugar must be then at
once poured out on an oiled marble slab, and either cut into pieces or
rolled into cylinders and twisted in the usual manner. One drop of oil of
citron, orange, or lemon, will flavour a considerable quantity. White
barley sugar is made with a strained decoction of barley instead of water,
or starch is added to whiten it.
=Sugar, Beet-root.= _Syn._ SACCHARUM BETÆ, L. Sugar obtained from the
white beet.
In the following table the names of the countries in which this plant is
cultivated are given, together with the amount of sugar annually produced
in each:
France 280,000 tons.[207]
Germany 260,000 ”
Austria and Hungary 180,000 ”
Russia and Poland 130,000 ”
Belgium 50,000 ”
Holland and other countries 17,000 ”
[Footnote 207: British Manufacturing Industries, Glanford.]
The white beet is used in preference to the red varieties, not only
because of the colour of its juice, but also in consequence of its being
richer in sugar. The roots vary in their yield of sugar according to
quality and the season of the year. They are generally in best condition
in October. The root is made up of a series of small cells, which are
filled with the saccharine fluid. According to Wagner the constituents of
the sugar-beet are as follows:
Water 82·7
Sugar 11·3
Cellulose 0·8
Albumen, casein, and other bodies 1·5
Fatty matter 0·1
Organic substances, citric acid, pectin, and pectic acid. Asparagin, }
aspartic acid, and betain, a substance having, according to }
Schiebler, the formula C_{15}H_{33}N_{3}O_{6} }
Organic salts, oxalate and pectate of calcium, oxalate and pectate }
of potassium and sodium } 3·7
Inorganic salts, nitrate and sulphate of potash, phosphate of lime }
and magnesia }
Twelve and a half hundred weight of beet yield on an average 1 cwt.
of raw sugar, or 8 per cent.
The first operation in the manufacture of beet-root sugar after washing
and cleansing the roots (an operation which sometimes reduces their weight
10 or 20 per cent.) is the extraction from them of the juice. This may be
effected either by:
1. Pressure.
2. Centrifugal power.
3. Dialysis.
1. _Pressure._ The roots being put into a proper crushing machine are soon
reduced to an uniform pulp, which in some manufactories is subjected to
pressure wrapped in linen cloths under stone or iron rollers, and in
others is placed in bags and placed under the Bramah or hydraulic press,
the resulting juice being collected in proper receptacles.
2. _Centrifugal power._ This method is that generally employed for
separating the juice from the pulp, which thus yields between 50 or 60 per
cent. of juice. A weak saccharine solution, also used in sugar
manufacture, is afterwards obtained by mixing the residue of the pulp with
water, and subjecting it to the same process.
3. _Dialysis._ The application of the principle of diffusion for the
extraction of the sugar from the beet-root originated with M. Robert. The
fresh roots, cut into thin slices, are immersed in a little more than
their own weight of water heated to about 120° F. The crystalloid sugar
thus diffuses out through the cell membrane which encloses it into the
surrounding water, leaving the pectous and colloid matters, such as
albumen, gum, &c., behind. The operation which is so managed as to bring
the same water into contact with successive quantities of root, yields a
saccharine solution of nearly the same strength as the natural juice. The
solution so obtained is, after concentration and the usual methods,
converted into sugar. The same process is said to have been tried with
cane sugar, and with equally satisfactory results.
The succeeding stages of the manufacture of beet sugar, such as refining,
liming, decolorising, &c., are the same as those already described under
cane sugar.
Beet sugar is in every respect identical with cane. It was discovered in
1747 by Marggraf, of Berlin, but it did not come into use until about the
beginning of the present century, its manufacture at this period in
France being necessitated by an edict of the first Napoleon’s, which
prohibited the importation of cane sugar into that country.
The engraving represents a vacuum pan much used in the French sugar
refineries.
Fig. 1 gives a perspective, and fig. 2 a sectional view of this
evaporating pan.
[Illustration: FIG. 1.]
[Illustration: FIG. 2.]
The boiling-pan (B) consists of two air-tight hemispheres, surmounted by a
funnel, connected by the tube (_l_) with the condenser (A). The apparatus
is supplied by steam by (_r s_), the steam circulating in the boiling-pan
by means of the pipes (_g_), fig. 2. By opening the lever valves (_f_) the
juice can be run by means of the pipe (_o_) into the pan (_p_). When the
pan, after continued boiling, requires to be refitted, the pipes (_l_ and
_w_) are connected to an air-pump. The manometer (_h_) shows the state of
the air pressure, which can be regulated by opening the pipes connected to
the vacuum chamber. By means of the gauge cylinder (G) the quantity of
syrup in the boiling-pan can be ascertained, the gauge cylinder being
connected to the boiling-pan by the pipes (_a_ and _i_), and the height
read off from the gauge tube (_n_). The syrup can be removed, for the
purpose of ascertaining its consistency, from the gauge cylinder by means
of either of the three pipes (_b_, _c_, _d_). By _u_ steam can be admitted
to the boiling-pan and condenser. _e_ is generally of stout glass, and
enables the state of the juice to be seen. _g_ is the grease cock, _f_ the
manhole. The condenser consists of the jacket (B), arranged to prevent the
mixing of the juice with the water used for condensation. _x_ is the
gauge. The pipe (_m_) conveying water to the condenser terminates in a
rose. _z_ is a thermometer showing the interior temperature of the
boiling-pan.
The air-pump being set in operation the tube (_c_) is opened, and the
gauge cylinder filled by the juice rising from _q_. By closing _m_ and
opening _y_ the juice is admitted to the boiling-pan. When this is half
full the steam pipe (_s_) is opened, the steam quickly heating the
contents of the pan to the boiling point. The condenser is then placed in
working; by opening the pipe (_l_) the steam of the juice passes into the
condenser, where it is speedily condensed, passing with the water through
β.
=Sugar, Diabet′ic.= Grape sugar found in the urine of persons labouring
under diabetes. In _diabetes insipidus_, a substance having the general
properties of a sugar, but destitute of a sweet taste, appears to be
produced (Thénard.)
=Sugar, Gel′atin.= See GLYCOCINE.
=Sugar, Grape=, C_{6}H_{12}O_{6}.H_{2}O. _Syn._ GLUCOSE, FRUIT SUGAR;
SACCHARUM UVÆ, S. FRUCTUS, L. This substance is found in the juice of
grapes and other fruit, in the urine of diabetic patients, and in the
liquid formed by acting on starch and woody fibre with dilute sulphuric
acid.
_Prep._ 1. From the juice of ripe grapes or an infusion of the ripe fruit
(raisins), by saturating the acid with chalk, decanting the clear liquid,
evaporating to a syrup, clarifying with white of egg or bullock’s blood,
and then carefully evaporating to dryness; it may be purified for chemical
purposes by solution and crystallisation in either water or boiling
alcohol. Like other sugar, it may be decoloured by animal charcoal.
2. From honey, by washing with cold alcohol, which dissolves the fluid
syrup and leaves the solid crystallisable portion.
_Prop._ It is less sweet and less soluble than cane sugar, requiring 1-1/2
part of cold water for its solution; instead of bold crystals, it forms
granular warty masses, without distinct crystalline faces; it does not
easily combine with either oxide of calcium or oxide of lead; with heat,
caustic alkaline solutions turn it brown or black, but it dissolves in oil
of vitriol without blackening, the reverse being the case with cane sugar;
with chloride of sodium it forms a soluble salt, which yields large,
regular, and beautiful crystals. Sp. gr. 1·400.
The various fruits contain grape sugar in the following proportions:
Per Cent.
Peach 1·57
Apricot 1·80
Plum 2·12
Raspberry 4·00
Blackberry 4·44
Strawberry 5·73
Bilberry 5·78
Currant 6·10
Plum 6·26
Gooseberry 7·16
Cranberry 7·45 (according to Fresenius).
Pear 8·02 to 10·8 (E. Wolff).
Apple 8·37 (Fresenius).
” 7·28 to 8·04 (E. Wolff).
Sour cherry 8·77
Mulberry 9·19
Sweet cherry 10·79
Grape 14·93
_Obs._ Cane sugar is converted into grape sugar during the process of
fermentation, and by the action of acids. See SUGAR, and SUGAR, STARCH
(_below_).
=Sugar, Maple.= _Syn._ SACCHARUM ACERINUM, L. From the juice of the sugar
maple. It is identical with cane sugar.
In the United States and the British Colonies of North America
considerable quantities of this sugar are made. The juice is obtained by
boring through the bark of the tree to a depth of about a quarter or half
an inch. Each tree has generally two perforations made in it, and they are
always made on that side of the tree which faces towards the south, and at
a distance of about 20 inches from the ground. The juice flows into
suitable vessels, into which it is conducted by reeds placed under the
perforations. The period chosen for tapping the trees is that during which
it is known the sap is ascending, from March to May. Sometimes the tree
undergoes a second tapping in the autumn, but this is not generally
practised, inasmuch as it is injurious to the tree. A daily yield of 6
galls, of juice from each incision is looked upon as a ‘good run,’ and if
this 6 gall. be the produce of an old tree or ‘old bush’ they will yield 1
lb. of sugar. In a young tree or ‘young bush’ the yield of sugar from the
same quantity of sap is only half. By proper care the same tree may be
tapped 20 or 30 years following. Unlike the sugar-cane the juice in the
maple is the richest in sugar the higher it is found from the ground. The
concentrated saccharine liquid is concentrated every 24 hours. The raw
crystallised sugar undergoes no refining, and being made into blocks is
then sent to market.
=Sugar, Milk.= C_{12}H_{22}O_{11}.H_{2}O. _Syn._ SUGAR OF MILK, LACTIN;
SACCHARUM LACTIS (Ph. D.), L. _Prep._ Gently evaporate clarified whey
until it crystallises on cooling, and purify the crystals by digestion
with animal charcoal and repeated crystallisations.
_Prop., &c._ White, translucent, very hard cylindrical masses or
four-sided prisms; soluble in about 6 parts of cold and in 2 parts of
boiling water; nearly insoluble in alcohol and ether; ammoniacal plumbic
acetate precipitates it from its solutions. When an alkaline solution of
grape sugar is boiled with the salts of copper, silver, or mercury, it
reduces them; it produces right-handed rotation of a ray of polarised
light; by boiling with dilute acid it is converted into _galactose_
(C_{6}H_{12}O_{6}); treated with nitric acid it yields mucic acid, with
small quantities of saccharic, oxalic, and tartaric acid. Milk sugar is
unsusceptible of the vinous fermentation, except under the action of
dilute acids, which convert it into grape sugar; in solution, it is
converted into lactic or butyric acid by the action of caseine and
albuminous matter. Milk contains about 5% of it. (Boussingault.)
_Obs._ Sugar of milk is chiefly imported from Switzerland. In this country
it is chiefly used as a vehicle for more active medicines, especially
among the homœopathists.
=Sugar, Starch.= _Syn._ POTATO SUGAR, FÆCULA S. This is grape sugar
obtained by the action of diastase on starch, in the manner noticed under
GUM (British), or by the action of dilute sulphuric acid on starch, or of
the strong acid on lignin, or on substances containing it.
_Prep._ 1. From corn. The corn is first steeped in soda lye; it is then
ground wet and passed through revolving sieves to separate the husks and
gluten. The starch is carried through long troughs, in which are placed
transverse pieces of wood, against which the solid particles of starch
lodge, and are thus separated from the washing waters. These wash waters
run into a large cistern, where it undergoes fermentation into weak
vinegar. The starch in the wet state is then put into a mash tub and
treated for from 3 to 8 hours with 1 per cent. of sulphuric acid. The acid
liquor is neutralised with chalk and evaporated in vacuum pans; and after
being separated from the sulphate of lime it is run into barrels and
allowed to crystallise. The grape sugar is sometimes manufactured in
blocks 6 inches square, and dried on plaster plates in a current of dry
air, as hot air would decolorise it. Large quantities of grape sugar
manufactured as above are now produced in the United States, particularly
in New Orleans, Buffalo, and Brooklyn. A considerable amount from the same
source reaches this country from the Continent, and is employed in our
breweries. When specially prepared for the use of the latter the blocks
are crushed into small pieces about the size of malt grains. Our excise
authorities prohibit the entrance of glucose into a brewer’s premises in
the liquid state. In the brewing of pale sparkling ales grape is esteemed
more than either cane sugar or malt, and is said to yield a more sound and
wholesome liquor, and one free from the acidity, impurity, and treacly
sweetness frequently found in beers brewed from raw or inferior sugars.
Glucose may also be obtained from cellulose, but the process is too
expensive to admit of being practically worked.
2. Potato starch, 100 parts; water, 00 parts; sulphuric acid, 6 parts;
mix, boil for 35 or 40 hours, adding water, to make up for evaporation;
then saturate the acid with lime or chalk, decant or filter, and evaporate
the clear liquor. Under pressure the conversion is more rapid. _Prod._
105%.
3. “The starch of potatoes can be converted into glucose by digestion for
a few hours with parings of the potato. This operation is largely
practised by German farmers in the preparation of food for fattening hogs.
An excellent starch sugar can be prepared from Indian corn, which will
yield alcohol one eighth cheaper, and quite as pure as that from cane
sugar.”[208]
[Footnote 208: ‘Journ. of Applied Chemistry.’]
4. Shreds of linen or paper, 12 parts; strong sulphuric acid, 17 parts
(Braconnot; 5 of acid, and 1 of water——Vogel); mix in the cold; in 24
hours dilute with water, and boil it for 10 hours; then neutralise with
chalk, filter, evaporate to a syrup, and set the vessel aside to
crystallise. _Prod._ 114%. Sawdust, glue, &c., also yield grape sugar by
like treatment. See LIGNIN.
=Sugar from other Sources.= Considerable quantities of East Indian cane
sugar are yielded by certain Indian palms, the principal of which are the
_Arenga saccharifera_ and the _Phœnix sylvestris_ or wild date. Another
source whence large quantities of cane sugar are procured is the _Sorghum
saccharatum_ or sugar grass. This plant is exclusively grown in Ohio, and
yields annually more than 15,000,000 gall. of juice, which is made into
sugar.
_Melezitose_ (C_{12}H_{22}O_{11}). From larch manna.
_Mycose_ or _trehalose_ (C_{12}H_{22}O_{11}). From Turkish manna.
_Melitose_ (C_{12}H_{24}O_{12}). From the eucalyptus.
_Maltose_ (C_{12}H_{24}O_{12}). From malt.
_Eucalen_ (C_{6}H_{12}O_{6}). By fermentation of melitose.
_Sorbin_ (C_{6}H_{12}O_{6}). From the berries of the service tree.
_Effects of the varieties of Sugar on Polarised Light._ Both sucrose, or
cane sugar, and dextrose produce rotation upon a ray of polarised light.
The plane of rotation is rotated to the right by sucrose rather more
powerfully than by dextrose. It is remarkable that the uncrystallisable
sugar of fruits produces an opposite rotation, viz. to the left. Since the
degree of rotation is proportionate in columns of equal length to the
quantity of sugar present, it has been proposed to employ this property in
order to determine the quantity of sugar present in syrups.[209] The
following, according to Berthelot, are the rotatory powers of the
different varieties of sugar, if equal weights of each are dissolved in an
equal bulk of water; the quantities of each sugar are calculated for the
formulæ annexed:
[Footnote 209: Miller.]
+----------------------+--------------------+-----------+-----------------+
| | | | Temperature. |
| Variety. | Formula. | Rotation. | |
| | | |° Fahr. |° Cent. |
+----------------------+--------------------+-----------+--------+--------+
| | | | | |
|Sucrose (cane sugar) |(C_{12}H_{22}O_{11})|Right 73·8°| | |
|Melezitose |(C_{12}H_{22}O_{11})| ” 94·1°| | |
|Mycose |(C_{12}H_{22}O_{11})| ” 193° | | |
|Melitose |(C_{12}H_{24}O_{12})| ” 102° | | |
|Dextrose (grape sugar)|(C_{6}H_{12}O_{6}) | ” 57·4°| | |
|Malt sugar |(C_{6}H_{12}O_{6}) | ” 172° | | |
|Lœvulose (fruit | | | | |
| sugar) |(C_{6}H_{12}O_{6}) |Left 106° | 56 | 13·3 |
|Eucalin |(C_{6}H_{12}O_{6}) |Right 50° | | |
|Sorbin |(C_{6}H_{12}O_{6}) |Left 46·9°| | |
|Lactose (milk sugar) |(C_{6}H_{12}O_{6}) |Right 56·4°| | |
|Glucose of ditto | | | | |
| (galactose) |(C_{6}H_{12}O_{6}) | ” 83·3°| | |
|Inverted cane sugar |(C_{6}H_{12}O_{6}) |Left 28° | 57 | 13·9 |
| | | | | |
+----------------------+--------------------+-----------+--------+--------+
=SUGAR-BOILING.= The art or business of the confectioner or sugar-baker;
the candying of sugar. The stages are as follow:——Well clarified and
perfectly transparent syrup is boiled until a ‘skimmer’ dipped into it,
and a portion ‘touched’ between the forefinger and thumb, on opening them,
is drawn into a small thread, which crystallises and breaks. This is
called a ‘weak candy height.’ If boiled again, it will draw into a larger
string, and if bladders may be blown through the ‘drippings’ from the
ladle, with the mouth, it has acquired the second degree, and is now
called ‘bloom sugar.’ After still further boiling, it arrives at the state
called ‘feathered sugar.’ To determine this re-dip the skimmer, and shake
it over the pan, then give it a sudden flirt behind, and the sugar will
fly off like feathers. The next degree is that of ‘crackled sugar,’ in
which state the sugar that hangs to a stick dipped into it, and put
directly into a pan of cold water, is not dissolved off, but turns hard
and snaps. The last stage of refining this article reduces it to what is
called ‘carmel sugar,’ proved by dipping a stick first into the sugar, and
then into cold water, when, on the moment it touches the latter, it will,
if matured, snap like glass. It has now arrived at a ‘full candy height.’
Care must be taken throughout that the fire is not too fierce, as, by
flaming up against the sides of the pan, it will burn and discolour the
sugar; hence the boiling is best conducted by steam heat.
Any flavour or colour may be given to the candy by adding the colouring
matter to the syrup before boiling it, or the flavouring essences when the
process is nearly complete. See STAINS, &c.
=SUGAR CAN′DY.= _Syn._ SACCHARUM CANDIDUM, S. CRYSTALLINUM, S.
CRYSTALLIZATUM, L. Sugar crystallised by leaving the saturated syrup in a
warm place (90 to 100° Fahr.), the shooting being promoted by placing
sticks, or threads, at small distances from each other in the liquor; it
is also deposited from compound syrups, and does not seem to retain much
of the foreign substances with which they are loaded. Brown sugar candy is
prepared in this way from raw sugar; white do., from refined sugar; and
red do., from a syrup of refined sugar which has been coloured red by
means of cochineal.
Sugar candy is chiefly used as a sweetmeat; and, being longer in
dissolving than sugar, in coughs, to keep the throat moist; reduced to
powder, it is also blown into the eye, as a mild escharotic in films or
dimness of that organ.
=SUGAR OF LEAD.= Acetate of lead.
=SUGAR PLUMS.= _Syn._ BON-BONS, DRAGÉES, Fr. These are made by various
methods, among which are those noticed under DROPS (Confectionery),
LOZENGES, and PASTILS, to which may be added the following:——Take a
quantity of sugar syrup, in the proportion to their size, in that state
called a ‘blow’ (which may be known by dipping the skimmer into the sugar,
shaking it, and blowing through the holes, when parts of light may be
seen), and add a drop or two of any esteemed flavouring essence. If the
‘bon-bons’ are preferred white, when the sugar has cooled a little, stir
it round the pan till it grains and shines on the surface. When all is
ready, pour it through a funnel into little clean, bright, leaden moulds,
which must be of various shapes, and be previously slightly moistened with
oil of sweet almonds; it will then take a proper form and harden. As soon
as the plums are cold, take them from the moulds; dry them for two or
three days in the air, and put them upon paper. If the bon-bons are
required to be coloured, add the colour just as the sugar is ready to be
taken off the fire.
CRYSTALLISED BON-BONS are prepared by dusting them with powdered
double-refined lump sugar before drying them.
LIQUEUR BON-BONS, now so beautifully got up by the Parisian confectioners,
are obtained by pressing pieces of polished bone or metal into finely
powdered sugar, filling the hollow spaces so formed with saturated
solutions of sugar in the respective liqueurs, and then spreading over
the whole an ample layer of powdered sugar. In the course of three or four
days the bon-bons may be removed, and tinted by the artist at will.
Instead of white powdered sugar ordered above, coloured sugar may be used.
These bon-bons are found to be hollow spheres, containing a small quantity
of the spirit or liqueur employed, and will bear keeping for many months.
See SWEETMEATS, &c.
=SUGARS (Medicated).= _Syn._ SACCHARIDES; SACCHARA MEDICATA, L.;
SACCHAROLÉS, SACCHARURES, Fr. Some of these are prepared by moistening
white sugar with the medicinal substance, then gently drying it, and
rubbing it to powder; in other cases they are obtained in the manner
noticed under PULVERULENT EXTRACTS, or OLEOSACCHARUM. The most valuable
preparation of this class in British pharmacy is the saccharated carbonate
of iron (FERRI CARBONAS CUM SACCHARO——Ph. L.).
=SUINT, Gas from.= By this is understood a gas prepared from the fatty
materials present in the soap-suds used in washing raw wool and spun
yarns. The water containing the suint and soap-suds is run into cisterns,
and is there mixed with milk of lime, and left to stand for twelve hours.
A thin precipitate is formed, which, after the supernatant clear liquor
has been run off, is put upon coarse canvas for the purpose of draining
off any impurities, sand, hair, &c., while the mass which runs through the
filter is put into a tank, in which it forms, after six or eight days, a
pasty mass, which, having been dug out and moulded into bricks, is dried
in open air. At Rheims the first wash-water of the wool is used for making
both gas and potash, because the water contains no soap and only suintate
of potash. Havrez, at Verviers, has recently proposed to employ
suint——which, by-the-bye, is very rich in nitrogen——for the purpose of
making ferrocyanide of potassium.
The dried brick-shaped lumps are submitted to distillation, yielding a gas
which does not require purification, and which possesses an illuminating
power three times that of good coal gas. The wash-water of a wool-spinning
mill with 20,000 spindles yields daily, when treated as described, about
500 kilos of dried suinter, as the substance is technically called. One
kilo of this substance yields 210 litres of gas. Annually about 150,000
kilos of suinter are obtained, and this quantity will yield 31,500,000
litres = 1,112,485 cubic feet of gas. Every burner consuming 35 litres of
gas per hour, and taking the time of burning at 1200 hours, the quantity
of gas will suffice for 750 burners, and as a spinning mill of 20,000
spindles only requires 500 burners, there is an excess of gas supply
available for 250 other burners, or the owner may dispose of 5000 kilos of
suinter, which is valued at Augsburgh at about 3s. per 50 kilos, and at
about 4s. at Mulhouse.[210]
[Footnote 210: Wagner’s ‘Chemical Technology.’]
=SUL′PHATE.= _Syn._ SULPHAS, L. A salt of sulphuric acid.
=SUL′PHIDE.= A salt consisting of sulphur and a metal or other basic
radical. See SULPHURETTED HYDROGEN.
=SULPHINDYL′IC ACID.= _Syn._ SULPHINDIGOTIC ACID. An intensely blue pasty
mass, formed by dissolving 1 part of indigo in about 15 parts of
concentrated sulphuric acid. See SULPHATE OF INDIGO.
=SUL′PHITE.= A salt of sulphurous acid.
=SULPHOCARBOLIC ACID.= (SULPHOCARBOLATES.) Carbolic acid, when acted upon
by bases, yields a class of salts termed carbolates. These compounds are
very unstable; they readily absorb water from the air, which sets free
carbolic acid; they usually have the powerful odour of the latter. When,
however, equivalent weights of carbolic and sulphuric acids are mixed,
union takes place, a definite double acid (sulphocarbolic) results, and
the salts formed by this double acid with the various bases are entirely
different from the simple salts of carbolic acid. They are very stable,
very soluble, possess neither odour nor taste of carbolic acid, and are
singularly beautiful in crystalline form.
=Sulphocarbolic Acid= (HC_{6}H_{3}SO_{4}) is obtained by the
crystallisation in long colourless needles; unlike carbolic acid, it is
soluble in water, alcohol, and ether, in any proportions.
=Sulphocarbolate of Calcium= [Ca(C_{6}H_{5}SO_{4})_{2} + Aq.] is obtained
in very long, fine, densely interlacing crystals, which form in bulk, by
their interlacement, a porous mass. Unlike the usual lime-salts, this is
exceedingly soluble. This fact overcomes the great difficulty of treatment
when in disease there is a deficiency of lime in the body, especially in
rickets, in which disease the want of lime in the bones gives rise to
distortions. The sulphocarbolate of magnesium crystallises in large,
clear, rhombic prisms, easily soluble in water.
=Sulphocarbolate of Copper= [Cu(C_{6}H_{5}SO_{4})_{2}] forms fine
prismatic crystals of a blue colour. It is used as the zinc
sulphocarbolate, chiefly as a lotion and dressing, in the proportion of 3
to 10 grains to the ounce of distilled water.
=Sulphocarbolate of Iron= [Fe(C_{6}H_{5}SO_{4})_{2}] is in colourless or
pale green rhombic plates. It is readily administered, and seems in some
instances to be preferred to other salts of iron. It seems to have been of
especial use in the skin diseases of children, wherein there is much
formation of matter.
=Sulphocarbolate of Sodium= [Na(C_{6}H_{5})SO_{4}.Aq] is in brilliant,
clear, rhombic prisms. The salt is very soluble in water. This salt can be
administered as a medicine in doses of 20 to 60 gr.; it is slowly
decomposed in the textures, carbolic acid being evolved. It thus becomes
a very simple means of obtaining the beneficial effects of the
administration of this antiseptic without the difficulties and dangers
which attend it in its uncombined irritant and caustic form. It has proved
of great service in the treatment of infectious diseases. Administered in
the severest cases of diphtheria, malignant scarlet fever, typhoid,
erysipelas, &c., the remedy has proved of extreme value.
=Sulphocarbolate of Zinc= [Zn(C_{6}H_{5}SO_{4})_{2}] is chiefly employed
in solution as a lotion. By high surgical authorities it is considered to
answer all the purposes of the antiseptic dressing of carbolic acid. It is
inodorous, and has very slight irritating action.
=The Sulphocarbolates of Potassium= [KC_{6}H_{5}SO_{4}] =and Ammonium=
[NH_{4}C_{6}H_{5}SO_{4}] are also brilliant crystals; they are freely
soluble, administered with the greatest ease, and have been used with
success as remedial agents.
=SULPHOCYAN′OGEN.= A well-defined salt radical, containing sulphur united
to the elements of cyanogen. Its compounds are the sulphocyanides, most of
which may be formed by directly saturating hydrosulphocyanic acid with the
oxide or hydrate of the base; or, from the sulphocyanide of potassium and
a soluble salt of the base, by double decomposition.
=SULPHOFORM.= _Syn._ SULPOFORMUM. An oily liquid obtained by distilling
one part of iodoform with three of sulphide of mercury.
=SULPHOPHE′NIC ACID.= A synonym of sulphocarbolic acid. See
SULPHOCARBOLATES.
=SULPHOVIN′IC ACID.= C_{2}H_{5}HSO_{4}. _Syn._ SULPHETHYLIC ACID; ACIDUM
SULPHOVINICUM, L. This substance is formed by the action of heat on a
mixture of alcohol and sulphuric acid; it is the intermediate product
which is developed in the preparation of ether. The salts are called
sulphovinates or sulphothylates.
=SUL′PHUR.= [Eng., L.] _Syn._ BRIMSTONE; SOUFRE, Fr. An elementary
substance. That of commerce is chiefly imported from Sicily and Italy, and
is a volcanic production.
_Var._ The principal of these are:
AMORPHOUS SULPHUR, BROWN S.; SULPHUR AMORPHUM, S. FUSCUM, S. INFORME, S.
RUBRUM, L. Prepared from sublimed sulphur, by melting it, increasing the
heat to from 320° to 350° Fahr., and continuing it at that temperature for
about half an hour, or until it becomes brown and viscid, and then pouring
it into water. In this state it is ductile, like wax, may be easily
moulded in any form, is much heavier than usual, and when it has cooled
does not again become fluid until heated to above 600° Fahr. The same
effect is produced more rapidly by at once raising the temperature of the
melted mass to from 430° to 480° Fahr.
PRECIPITATED SULPHUR, HYDRATE OF SULPHUR, MILK OF S.; SULPHURIS HYDRAS,
LAC SULPHURIS, SULPHUR PRÆCIPITATUM (Ph. L.). _Prep._ 1. From sublimed
sulphur, 1 part; dry and recently slaked lime, 2 parts; water, 25 parts,
or q. s.; boil for 2 or 3 hours, dilute with 25 parts more of water,
filter, and precipitate with dilute hydrochloric acid; drain, and well
wash the precipitate, and dry it by a gentle heat. Resembles sublimed
sulphur in its general properties, but is much paler, and in a finer state
of division.
2. (B. Ph.) Sublimed sulphur, 5 oz.; slaked lime, 3 oz.; hydrochloric
acid, 3 fl. oz., or q. s.; distilled water, q. s. Heat the sulphur and
lime, previously well mixed, in 1 pint of water, stirring diligently with
a wooden spatula, boil for 15 minutes and filter. Boil the residue again
in 1/2 pint of water and filter. Let the united filtrates cool, dilute
with 2 pints of water, and in an open place, or under a chimney, add in
successive quantities the hydrochloric acid previously diluted with 1 pint
of water until effervescence ceases, and the mixture acquires an acid
reaction. Allow the precipitate to settle, decant off the supernatant
liquid, pour on fresh distilled water, and continue the purification by
affusion of distilled water and subsidence, until the fluid ceases to have
an acid reaction, and to precipitate with oxalate of ammonia. Collect the
precipitated sulphur on a calico filter, wash it once with distilled
water, and dry it at a temperature not exceeding 120° Fahr.
_Prop._ A greyish-yellow powder free from grittiness, and with no smell of
sulphuretted hydrogen.
_Obs._ Many pharmacists regard LAC SULPHURIS and SULPHUR PRECIPITATUM as
distinct substances, and assume that by milk of sulphur is intended a
preparation made by an old pharmacopœial process, in which sulphuric acid
being employed, the sulphur so precipitated contains from 50 to 75 per
cent. of sulphate of lime. Pareira, Royle, Atfield, and some other
authorities, hold that LAC SULPHURIS and SULPHUR PRECIPITATUM are
synonymous; whilst others, including Professor Redwood (one of the
compilers of the B. P.) entertain a contrary opinion.
ROLL SULPHUR, CANE S., STICK S.; SULPHUR IN BACCULIS, S. IN ROTULIS, S.
ROTUNDUM, L. This is crude sulphur, purified by melting and skimming it,
and then pouring it into moulds. That obtained during the roasting of
copper pyrites, and which forms the common roll sulphur of England,
frequently contains from 3 to 7% of yellow arsenic.
SUBLIMED SULPHUR, FLOWERS OF SULPHUR; FLORES SULPHURIS, SULPHUR (Ph. L.),
SULPHUR SUBLIMATUM (B. P., Ph. E. & D.), L. Prepared by subliming sulphur
in iron vessels. For medical purposes, it is ordered to be well washed
with water, and dried by a gentle heat. “A slightly gritty powder, of a
fine greenish-yellow colour, without taste and without odour till
heated.” (B. P.)
SULPHUR VIVUM, BLACK SULPHUR, CRUDE S., HORSE BRIMSTONE; SULPHUR NIGRUM,
S. CABALLINUM, S. GRISEUM, L. This is crude native sulphur. It is a grey
or mouse-coloured powder. The residuum in the subliming pots from the
preparation of flowers of sulphur is now commonly substituted for it. It
generally contains much arsenic, and is consequently very poisonous.
_Pur._ The sublimed sulphur of the shops is now, in general, of
respectable quality, but the precipitated sulphur frequently contains
about 2/3 of its weight of sulphate of lime (plaster of Paris), owing to
the substitution of sulphuric acid for hydrochloric acid in its
manufacture.[211] This is readily detected by strongly heating a little of
the suspected sample in an iron spoon or shovel, when the sulphur is burnt
or volatilised, and leaves behind the sulphate of lime as a white ash;
this, when mixed with water, and gently dried, gives the amount of the
adulteration. A still simpler plan is to dissolve out the sulphur in the
sample with a little hot oil of turpentine or liquor of potassa; the
undissolved portion is foreign matter.
[Footnote 211: See PRECIPITATED SULPHUR, above.]
_Prop._ Sulphur melts to a clear thin fluid, and volatilises at about 232°
Fahr., and in open vessels rapidly takes fire, burning with a bluish
flame. It is insoluble in both water and alcohol; it is soluble in oil of
turpentine and the fatty oils, and freely so in bisulphide of carbon and
hot liquor of potassa. With oxygen it unites to form sulphurous anhydride,
and with the metals to form sulphides. Sp. gr. 1·982 to 2·015.
_Estim._ The determination of the quantity of sulphur, phosphorus, and
chlorine, in a state of combination, especially in organic mixtures, is
often rather troublesome. The proportion of sulphur is best determined by
oxidising a known weight of the substances by strong nitric acid, or by
fusing it in a silver vessel with 10 or 12 times its weight of pure
hydrate of potassa and about half as much nitre. The sulphur is thus
converted into sulphuric acid, the quantity of which can be determined by
dissolving the fused mass in water, acidulating the solution with nitric
acid, adding a salt of baryta, and weighing the resulting sulphate.
Phosphorus is, in like manner, oxidised to phosphoric acid, the quantity
of which is determined by precipitation in combination with sesquioxide of
iron, or otherwise. The chlorine is correctly determined by placing a
small weighed portion in a combustion-tube, which is afterwards filled
with fragments of pure quicklime. The lime is then brought to a red heat,
and the vapour of the liquid driven over it, when chloride of calcium is
formed. The contents of the tube, when cold, are dissolved in dilute
nitric acid, filtered, the chlorine precipitated by nitrate of silver, and
the chlorine weighed under the form of chloride of silver. See ORGANIC
SUBSTANCES.
_Uses, &c._ Sulphur is extensively used in the manufacture of gunpowder,
in bleaching, &c., &c. When swallowed, it acts as a mild laxative and
stimulating diaphoretic; and has hence been long taken in various chronic
skin diseases, in pulmonary, rheumatic, and gouty affections, and as a
mild purgative in piles, prolapsus ani, &c. Externally, it is extensively
used in skin diseases, especially the itch, for which it appears to be a
specific.——_Dose_, 20 to 63 gr., in sugar, honey, treacle, or milk.
=Sulphur, Chlo′′rides of.= Several of these compounds exist but the
following are the most important. 1. (DICHLORIDE, S_{2}Cl_{2}.) Prepared
by passing dry chlorine gas over the surface of sulphur melted in a
bulbed-tube or small retort connected with a well-cooled receiver. The
product is a deep orange-yellow and very mobile liquid, which possesses a
disagreeable odour, and boils at 280° Fahr. It is soluble in bisulphide of
carbon, and in benzol, without decomposing. It dissolves sulphur in large
quantities, especially when heated. A solution of the dichloride with
excess of sulphur in crude benzol is used for vulcanising caoutchouc.
2. (CHLORIDE, HYPOCHLORIDE, or HYPOCHLORITE of the shops; SULPHURIS
CHLORIDUM, S. HYPOCHLORIDUM, S. HYPOCHLORITIS, L.) This is prepared by
spreading washed sulphur thinly on the bottom of a wooden box, or other
chamber, and passing chlorine gas slowly over until it ceases to be
absorbed.
_Obs._ This last compound is of variable and undetermined constitution. It
has been recommended for internal use, by Derksengi, in old gouty
affections, combined with pains in the stomach, and in severe nervous
fever.——_Dose_, 1/2 to 2 gr.; dissolved in ether, and taken with old
Hungary wine. It is also used externally in _psoriasis inveterata_, and
other skin diseases.
=Sulphur, I′odide of.= S_{2}I_{2}. _Syn._ BINIODIDE OF SULPHUR; SULPHURIS
IODIDUM (Ph. L.), SULPHUR IODATUM (Ph. D.), L. _Prep._ Into a glass flask
put 1 part of sublimed sulphur, and over it place 4 parts of iodine;
insert the cork loosely, and place the flask in a water bath; as soon as
its contents melt, stir them with a glass rod, replace the cork, remove
the bath from the fire, and let the whole cool together. When cold, break
the iodide into pieces, and place it in a wide-mouthed stoppered bottle.
In this way a beautiful semi-crystalline, dark grey mass, resembling
antimony, is obtained. The formulæ of the B. P., Ph. L., E., & D., Ph. U.
S., & P. Cod., are essentially similar. The Ph. D. orders the two
substances to be powdered and mixed before heating them.
_Uses, &c._ It is stimulant and alterative. An ointment made of it has
been recommended by Biett and others in tuberculous affections of the
skin, in lepra, psoriasis, lupus, porrigo, &c.
Iodide of sulphur stains the skin like iodine, and is readily decomposed
by contact with organic substances.
=SULPHURA′TION.= The process by which silk, cotton, and woollen goods,
straw plait, &c., are subjected to the fumes of burning sulphur, or
sulphurous acid, for the purpose of bleaching or decolouring them. On the
large scale, this is effected in closed apartments, called ‘sulphuring
rooms,’ to which sufficient air only is admitted to keep up the slow
combustion of the sulphur. On the small scale, as for straw hats, bonnets,
&c., a large wooden chest is frequently employed in the same way.
=SUL′PHURET.= _Syn._ SULPHIDE; SULPHURETUM, SULPHIDUM, L. See SULPHIDE.
=SULPHURET′TED HY′DROGEN= (H_{2}S). _Syn._ HYDROGEN SULPHIDE, DIHYDRIC
SULPHIDE, HYDRIC SULPHIDE; HYDROSULPHURIC ACID. Sulphuretted hydrogen
occurs in nature amongst the gaseous products given off by volcanoes, as
well as in many mineral waters, amongst which may be instanced those of
Harrogate, in England, of Moffat, in Scotland, and of Barèges, Eaux
Bonnes, St. Sauveur, &c., in the Pyrenees. It is also evolved from
decaying animal matter containing albumen, such as white-of-egg, as well
as from putrisable animal and vegetable substances, when in contact with a
soluble sulphate, and is always one of the gases present in the air of
drains and sewers. Sulphuretted hydrogen may be procured by the direct
union of hydrogen and sulphur, as by passing hydrogen into boiling
sulphur. But this method of procuring it is rarely, if ever, adopted. The
much readier process of acting upon a metallic sulphide by an acid
constitutes the means by which the chemist almost invariably obtains this
gas.
The details of the process are as follows:
1. About an ounce of ferrous sulphide, previously reduced to small pieces,
is placed in a bottle, and then there is poured on to it a fluid ounce of
sulphuric acid diluted with 8 times its bulk of water, when the following
reaction ensues:——FeS + H_{2}SO_{4} = H_{2}S + FeSO_{4}.
The gas which is immediately and copiously given off may be collected in
an apparatus, a drawing and description of which are given below.
[Illustration]
The diluted acid, having become cool, is poured through the bulb-shaped
aperture down the glass tube upon the ferrous sulphide, and the evolved
gas passing through the small intermediate wash-bottle into the bottle at
the reader’s right hand, is absorbed by the water therein contained, the
operation being continued until the water has become saturated with the
gas. The glass tubes are connected with vulcanised india rubber, as shown
in the above plate. Diluted hydrochloric acid is frequently substituted
for sulphuric.
2. In the above process, the gas obtained, owing to the contamination of
the iron sulphide, is more or less impure. When sulphuretted hydrogen is
required in a state of purity, 1 oz. of antimonious sulphide must be
employed instead of the iron sulphide, and instead of sulphuric 3 or 4
parts of hydrochloric acid. As heat must be applied to the mixture, it
will be necessary to substitute a flask for the larger bottle, and to
support it on a retort stand. In other respects the apparatus needs no
alteration.
3. Sulphuretted hydrogen is also obtainable when paraffin is heated at a
moderately elevated temperature with sulphur, the reaction being attended
with an abundant evolution of the gas, and a simultaneous separation of
carbon.
⁂ The solution of sulphuretted hydrogen, which is so indispensable to the
chemist, and consequently in such constant requisition in the laboratory,
unfortunately very quickly decomposes into water, and sulphur, which
deposits at the bottom of the vessel containing it. To diminish as much as
possible the tendency to deterioration, the solution should be made either
with boiled water, or with the clear spoilt solution.
_Qualities, &c._ Sulphuretted hydrogen is a colourless inflammable gas,
somewhat heavier than air, its specific gravity being 1·174. When ignited,
it burns with a bluish flame, to water and sulphurous anhydride if the
combustion take place in a sufficient quantity of air, but if the supply
of air be too limited, sulphur is deposited. Under a pressure of 17
atmospheres it is condensed to a colourless and very mobile fluid, which
boils at 79·6° F., and freezes at 72·8° F. to a transparent solid. Both
the gas and its aqueous solution exercise a feebly acid reaction on
litmus.
Sulphuretted hydrogen is highly poisonous; when inhaled in any quantity it
causes fainting; and in smaller quantities, even when considerably diluted
by air, if breathed for any length of time, it acts as a dangerous
depressant and insiduous poison. Upon the lower animals it acts with fatal
rapidity, even if diluted with 800 or 1000 parts of atmospheric air.
Transmitted through tubes heated to redness, sulphuretted hydrogen becomes
partially decomposed into its elements, hydrogen and sulphur. Water at 32°
F. takes up 4·37 times its bulk of this gas, and at 59, 3·23 times its
hulk, hence the importance of collecting it, over warm water, if required
in the gaseous form.
In the presence of moisture, sulphurous anhydride and sulphuretted
hydrogen, if equivalent quantities of each react upon each other, become
decomposed into sulphur, water, and pentathronic acid; hence the value of
sulphurous acid as a disinfectant. The deposited sulphur is found always
to occur in the electro-positive condition. Chlorine, bromine, and iodine,
also decompose sulphuretted hydrogen with deposition of sulphur, and
formation of hydrochloric, hydrobromic, and hydriodic acids.
_Hydrosulphates or Sulphides._ Sulphuretted hydrogen or hydrosulphuric
acid, as it is sometimes called, when brought into contact with bases in
solution, gives rise to compounds, which by some chemists are regarded as
hydrosulphates, or combinations of the base with hydrosulphuric acid; and
by others as sulphides or combinations of the metal with sulphur, the
latter reaction being attended with the elimination of water, as when a
base is acted upon by hydrochloric acid. By those who hold the former view
the reaction would be as follows:
K_{2}O + H_{2}S = K_{2}O_{1}H_{2}S.
In the latter case it would be thus represented:
K_{2}O + H_{2}S = K_{2}S + H_{2}O.
The latter is the more general opinion, and it receives support from the
fact that when sulphuretted hydrogen is passed into the solution of a
metallic salt, an insoluble precipitate of a sulphide of the metal is
thrown down. Thus, when the gas is passed into a solution of cupric
sulphate, the precipitate consists of hydrated cupric sulphide, the
liberated sulphuric acid renders the liquid which was before neutral,
acid. The larger number of sulphides so formed, combining with water at
the instance of their precipitation, occur as hydrates.
There is also a class of sulphides known as hydrosulphides, sulphydrates,
or double sulphides, in which an equivalent of the metal is replaced by an
equivalent of hydrogen. Examples of these are the potassic hydrosulphide
(KHS), sodic hydrosulphide (NaHS), and ammonic hydrosulphide (H_{4}NHS).
No such combinations occur with hydrogen and the metals of the earth
proper, and of the iron group.
_Tests._ Many of the hydrosulphates or sulphides may be detected, by
dropping on them some hydrochloric acid, when the characteristic smell of
sulphuretted hydrogen will be immediately evolved from them. Very small
quantities of a sulphide may be detected as follows:——Place the suspected
sulphide in a small test tube, on the upper part of which is inserted a
piece of blotting paper moistened with a solution of plumbic acetate, then
carefully pour some hydrochloric acid on to the substance, when, if it be
a sulphide, the paper will become. immediately browned or blackened.
Many small quantities of the soluble sulphides are revealed in neutral or
alkaline solutions by the rich purple colour which they form on the
addition of a solution of sodic nitro-prusside. Most of them, when heated
before the blow-pipe, give off the smell of sulphurous acid.
The quantitative determination of free sulphuretted hydrogen, or of a
soluble sulphide in any solution, is conducted as follows:——The liquid to
be tested is mixed with a small quantity of a cold solution of starch,
made slightly acid with acetic acid. A solution of iodine of known
strength, dissolved in potassic iodide is then added, until the liquid
just begins to turn blue from the action of the excess of iodine on the
starch. In this process the sulphuretted hydrogen converts the iodine into
hydriodic acid, whilst sulphur is liberated.
Of course the quantity of sulphuretted hydrogen is calculated from the
quantity of iodine employed. The reaction is——
2H_{2}S + 2I_{2} = 4HI + S_{2}.
The value of sulphuretted hydrogen as a reagent has already been alluded
to. It throws down most of the metals from solutions of their salts in the
form of insoluble sulphides; and each of the sulphides so produced in many
cases being distinguished from the others by a special and characteristic
colour. The sulphuretted hydrogen thus presents the metal in a form in
which it can, in many instances, be easily and with certainty recognised.
Thus sulphide of lead is black, of arsenic yellow, of antimony orange, of
manganese salmon colour, and of zinc white. By means of sulphuretted
hydrogen, also, the chemist is enabled to separate the metals into groups.
For instance, from solutions containing certain metallic salts,
sulphuretted hydrogen throws down the metals as sulphides, provided the
solution has been previously made slightly acid. Copper, arsenic, tin, and
cadmium, are some of the metals thrown down under these conditions.
The salts of iron, nickel, cobalt, and certain others, although they do
not yield precipitates under like circumstances, are found to do so if
their solutions are made alkaline instead of acid. Again, there are other
salts, those of the alkalies and alkaline earths, which, when sulphuretted
hydrogen is passed through these solutions, give no precipitates either in
acid or alkaline solutions. The chemist, therefore, in the course of an
analysis, frequently avails himself of a knowledge of these facts to
separate certain metals from each other.
=Hydrogen, Persulphide of.= _Syn._ HYDRIC PERSULPHIDE, HYDROGEN
DISULPHIDE. To procure this substance, calcium disulphide (CaS_{2}) in
solution is poured into hydrochloric acid diluted with twice its bulk of
water. The solution being gently warmed, the persulphide subsides at the
bottom as an oily fluid. Hydric persulphide has a great resemblance to
hydric peroxide in qualities. It bleaches, and is decomposed, with
violence, when brought into contact with the oxides of manganese and
silver. It easily decomposes into sulphur and sulphuretted hydrogen.
=SULPHU′RIC ACID.= H_{2}SO_{4}. _Syn._ OIL OF VITRIOL, BRITISH O. OF V.,
VITRIOLIC ACID†; ACIDUM SULPHURICUM (B. P., Ph. L. & E.), ACIDUM
SULPHURICUM VENALE (Ph. D.), ACIDUM VITRIOLICUM†, L. This acid, in a
concentrated form, was discovered by Basil Valentine towards the end of
the 15th century. At first it was obtained by the distillation of green
vitriol, but is now made by the oxidation of sulphurous anhydride,
obtained by the combustion either of sulphur or of certain sulphides. In
consequence of the growing demand for sulphur in the manufacture of
gunpowder, ultramarine, and for the destruction of the vine parasites in
the vineyards of France, Italy, and Spain, sulphuric acid is now seldom
made by burning sulphur, but, with few exceptions, by roasting iron
pyrites, or bisulphide of iron.
The following table will convey an idea of the enormous consumption of
this mineral in vitriol making in England alone. The quantities given
represent tons.
+-----+-----------------------------------------------------------+-------+
| | Pyrites from[212] | |
|Date.+-------+--------+--------+---------+--------+------+-------+ Sum |
| |Norway.|Germany.|Belgium.|Portugal.| Spain. |Italy.|Sundry |Total. |
| | | | | | | |Places.| |
+-----+-------+--------+--------+---------+--------+------+-------+-------+
|1862 | 4,975 | 6,817 | 9,860 | 53,296 | 33,717 | ... | 2,187 |110,852|
|1863 | 6,736 | 15,409 | 12,059 | 109,180 | 33,213 | ... | 2,628 |179,225|
|1864 |16,087 | 12,751 | 7,069 | 118,489 | 15,529 | ... | 1,065 |170,990|
|1865 |22,229 | 14,727 | 2,121 | 137,787 | 16,393 | ... | 369 |193,626|
|1866 |38,262 | 21,574 | 4,006 | 165,993 | 11,910 | ... | 1,625 |244,596|
|1867 |77,895 | 34,592 | 2,299 | 105,556 | 50,222 | ... | 2,134 |272,698|
|1868 |63,007 | 41,559 | ... | 75,883 | 47,458 | 794 | 1,019 |229,720|
|1869 |63,091 | 13,983 | ... | 140,805 | 99,648 | ... | 2,420 |319,947|
|1870 |67,464 | 14,914 | ... | 174,459 |150,990 | ... | 3,676 |411,512|
|1871 |74,416 | 12,809 | ... | 120,573 |242,163 | ... | 4,581 |454,542|
|1872 |71,665 | 5,682 | ... | 180,329 |257,429 | ... | 2,521 |517,626|
+-----+-------+--------+--------+---------+--------+------+-------+-------+
[Footnote 212: “Development of the Chemical Arts during the last Ten
Years,” by Dr A. W. Hofman (‘Chemical News,’ vol. xxv, 1879).]
Of the other sulphides employed in vitriol making may be mentioned galena,
or native sulphide of lead, which, when roasted, is made to give up half
its sulphur. The chief consumption of this mineral is in the Harz. Copper
pyrites is also used in the Harz, as well as in Swansea and Glasgow.
Blende, or native sulphide of zinc, is also occasionally had recourse to.
In addition to the above sulphides, the vitriol maker in England, France,
and Germany has lately largely availed himself of a compound known as
‘Laming’s mixture,’ which is an impure oxide of iron that has been used in
gas manufacture for the removal from the gas of the sulphur. Laming’s
mixture is consequently rich in this last element.
Associated with the pyrites in small quantities are various substances,
some of which, becoming volatilised when the ore is burnt, enter the
chambers with the mixed gases, and thus find their entrance into the acid,
whilst others remain behind in the iron residue of impure ferric oxide,
left on the hearth of the furnace after roasting. The former of these
foreign bodies, which are found in most commercial acids, are described
below under the section “Purification.” Amongst the solid non-volatile
matters, the extraction of which from the burnt iron has been found in
many works to yield a profit, are zinc, copper, silver and thallium.
At Wolcrum, in Germany, the zinc which exists in the residue in the form
of sulphate is extracted by lixiviation, and then treated with common
salt, the reaction giving rise to the production of sulphate of soda and
chloride of zinc. The soda obtained is sufficient to pay for the working
of the operation, whilst a good profit is made by the sale of the large
quantities of chloride of zinc which are thus yielded.[213]
[Footnote 213: Ibid.]
The copper, which in some residues is met with to the amount of 4 per
cent., also pays for extraction, and is sold to the smelter. It is first
converted into chloride, and then precipitated by iron. The silver is
recovered by Claudet’s process, which consists in precipitating it from a
saline solution in which it is in the state of a soluble chloride, by
iodide of potassium.
In the Widnes Copper Works the silver so extracted yields an annual profit
of £3000.[214]
[Footnote 214: Ibid.]
Thallium is found in the fine dust caused by the combustion of the
pyrites, which dust deposits in the flues between the furnace and the
chambers. The metal is extracted from the dust by treating this latter
with dilute sulphuric acid. The resulting sulphate is converted into
chloride, and again reconverted alternately into sulphate and chloride
several times, the sulphate last obtained being reduced by metallic
zinc.[215]
[Footnote 215: Ibid.]
Selenium is also a frequent constituent in the flue dust. Some ores, after
being subjected to roasting, yield iron capable of being worked. This is
more particularly the case with the Spanish and Portuguese pyrites.
The following is an outline of the process by which sulphuric acid is
obtained, and of the chemical changes which occur during its manufacture:
The sulphur or sulphide being placed on the hearth of the furnace, shown
at A in the accompanying cut, when heated from below, soon takes fire, and
combining with the oxygen of the atmospheric air, the admission of which
into the furnace is regulated by an experienced workman, by the door shown
in the plate, forms sulphurous anhydride. An iron pot, standing on the
hearth of the furnace, contains a mixture of nitrate of soda and oil of
vitriol, and this becoming heated by the burning sulphur, decomposition of
the salt ensues, and fumes of nitric acid are given off. The sulphurous
anhydride and nitric acid gases thus formed together with air are carried
into large leaden chambers, standing on, and supported by, massive
frameworks of stout timber. Steam is admitted continuously by several jets
(see plate) into these chambers, which are covered at the bottom with
water to a depth of about three inches.
As soon as the mixed gases enter the chamber and come into contact with
the steam, the sulphurous anhydride acts on the nitric acid, forming
sulphuric acid, which falls into and is absorbed by the water on the floor
of the chamber, and nitric oxide, which is liberated in the chamber.
The following equation will illustrate the reaction:
2HNO_{3} + 3SO_{2} + 2H_{2}O = 3H_{2}SO_{4} + 2NO.
170 parts by weight of nitrate of soda are required to oxidise to
sulphuric acid 96 parts of sulphur, whereas rarely more, and frequently
less, than 5 parts of soda are required by the vitriol maker. This saving
of material is effected by the function performed in the chamber by the
nitric oxide resulting from the decomposition of the nitric acid.
The nitric oxide reacting upon the air in the chamber abstracts oxygen
from it and becomes converted into nitric peroxide, thus:
2NO + O_{2} = 2NO_{2}.
Nitric peroxide is a very unstable compound, and directly it comes into
contact with the fresh sulphurous anhydride entering the chamber, it
oxidises it in the presence of water to sulphuric acid, thus:
2NO_{2} + 2SO_{2} + 2H_{2}O = 2H_{2}SO_{4} + 2NO.
This deportment of the nitric oxide being continuous, it will be seen it
acts the part of a carrier of oxygen from the atmospheric air contained in
the chamber to the sulphurous acid, and by so doing (theoretically)
renders any further supply of nitrate of soda than that required to start
the process unnecessary.
As soon as the water, or rather liquid acid on the floor of the leaden
chambers, has acquired the sp. gr. of 1·35 to 1·50, it is drawn off, and
concentrated by boiling in shallow leaden pans to the density of about
1·72, after which it is further concentrated in green-glass or platinum
retorts, until the sp. gr. reaches 1·842 to 1·846. When of sp. gr. from
1·35 to 1·50 it is called chamber acid, and when of the last strength, is
used in the manufacture of salt-cake, sulphate of ammonia, some kinds of
manure, and nitric acid. Sulphuric acid of sp. gr. 1·720 is mostly
employed in the preparation of superphosphate of lime. After concentration
to 1·842 or 1·846, the clear acid is put into large globular bottles of
green glass (carboys), surrounded with straw and basket-work, and is sent
into the market under the name of ‘oil of vitriol.’
The leaden chambers in which the chemical changes take place, that result
in the formation of the acid, vary greatly in dimensions in different
works, being sometimes as much as 12 or 15 feet high, 15 or 20 wide, and
from 150 to 300 feet long. They are mostly partially divided by incomplete
leaden partitions, known as curtains, so arranged on the roof and the
floor as to cause the currents of mixed gases to come into collision, and
thus cause their admixture. Where there are a number of small separate
chambers they are connected by means of leaden tubes. A chamber having a
capacity of 25,000 cubic feet will yield 10 tons of acid weekly.
The sheets of lead used in the construction of the chambers are united by
fusion, or melting together of their edges. If cement were used it would
be speedily attacked and destroyed by the acid and gaseous products.
The process for the manufacture of sulphuric acid above described, was
devised in 1774 by a calico printer of Rouen, and improved by Chaptal.
In 1776 the first vitriol factory was set up at Prestonpans, by Dr
Roebuck, of Birmingham, with whom originated the idea of the leaden
chambers.
Various attempts have been at different times unsuccessfully made to
supersede the old process. Of these we may mention:
1. The proposal to oxidise sulphurous acid by means of chlorine in the
presence of steam.
2. Persoz’s method to oxidise sulphurous acid by means of nitric acid, and
to regenerate the nitric oxide resulting from the reduction of the acid by
the oxygen of the air in the presence of steam.
3. _a_, by the decomposition of gypsum by superheated steam at a red heat;
or _b_, by decomposing the gypsum by chloride of lead.
The failure of the above and other efforts has led to the chemist turning
his attention to the elaboration and perfection of the old process, in the
working of which considerable improvements have been introduced within the
last ten or fifteen years; improvements resulting not only in a diminished
cost of production, but in the manufacture of a purer, and therefore
better acid.
The proper construction of the furnaces, ovens, and grates on which the
firing of the sulphur or pyrites takes place, together with the flues, is
an important condition in the manufacture of the acid; and to this end a
great deal of scientific knowledge and experience have lately been applied
with excellent effect. Of the many improvements in this direction for
burning poor ores of pyrites is a contrivance much used in Germany, where
the furnace on which it is carried out is known as Gerstenhöfer’s oven. It
is shown in the accompanying drawing.
[Illustration]
The furnace is fitted inside with a number of little fire-clay
projections, arranged as shown in the plate, in banks or terraces, the
function of which is to prolong the exposure of the pyrites to heat. The
furnace having been previously raised to a red heat, by means of a coal or
wood fire (which is then extinguished), the pyrites are admitted into it
through the hoppers (_a_). At the base of the hoppers are grooved iron
rollers, which crush the lumps of ore as they enter the chambers, and by
thus reducing their size, expose a larger amount of surface to the action
of heat. The greater part of the sulphur of the pyrites is thus burnt off,
as the lumps pass from terrace to terrace, the heat at the same time
generated by their combustion being sufficient to keep up that of the
furnace. A moderate blast of air is admitted at _c_, whilst the sulphurous
acid formed ascends through _d_ into the leaden chambers, the spent
pyrites falling out through the apertures at _c_.
Another improved furnace is Perret’s, which is largely used in France. In
this, small lumps of pyrites are placed on horizontal plates, and exposed
to the hot gases generated in kilns below. The gases, on their way to the
chambers, sweep over the pyrites and rob them of their sulphur.
The most important and noticeable improvement, however, of late years in
sulphuric acid manufacture is that resulting from the addition to the
plant of a contrivance of Gay-Lussac. Previous to this invention, the
sulphuric acid of commerce, amongst other impurities, always contained
appreciable quantities of certain oxides of nitrogen, the results of which
were not only the contamination of the acid, but a waste of substances,
which, properly utilised, are essential for the conversion of the
sulphurous and sulphuric acid, and the loss of which leads to an increased
consumption of nitrate of soda. Under the old method, these valuable
oxides of nitrogen, which, with a large amount of nitrogen and a small
quantity of oxygen, constituted the spent air of the last leaden chamber,
were carried off into the air, and consequently lost. Now, instead of
being allowed to diffuse into the atmosphere, they are made to pass
through a tower or chamber (shown at C in the plate below) filled with
coke, through which a thin stream of sulphuric acid is made to trickle. In
passing through the coke, therefore, the expiring spent gases come into
contact with the sulphuric acid, to which they give up their oxides of
nitrogen. From the tower (C) the acid flows into a cistern (D), whence it
is pumped up to the top of another tower (E), either filled with coke, or
arranged with inclined shelves, as shown in the plate. In this tower the
acid meets with a current of hot sulphurous acid and air coming up from
the furnace, which deprive it of the oxides of nitrogen, and the gaseous
mixture enters the chambers, whilst the denitrafied acid flows off into a
suitable reservoir.
[Illustration]
Since the introduction of the above, the consumption of nitrate of soda is
sometimes lessened by more than half.
Another very recent improvement, the invention of a German chemist named
Sprengel, is the substitution of water spray, blown in by steam, for steam
jets, in the leaden chambers. By this method a saving of coal to the
extent of one third is said to be effected.
In theory, 1 molecule of sulphur requires only 3 molecules of oxygen to
convert it into sulphuric acid, viz. 2 to form sulphurous anhydride, and 1
to convert the latter into sulphuric anhydride, which combines with 1
molecule of water to form the acid. Thus, 1 kilogram of sulphur requires
1500 grams or 1055 litres of oxygen, which is equivalent to 5275 litres of
air containing 4220 litres of nitrogen; when pyrites is used, a far larger
quantity of air is required, for the obvious reason that the pyrites
becomes converted into ferric peroxide. 1 kilogram of pyrites requires for
its combustion nearly 6600 litres of air.
In well-regulated works the spent and escaping gases should not contain
more than 2 per cent. of oxygen. If from 100 kilograms of sulphur 306
kilograms of strong acid of sp. gr. 1·84 be obtained, the result is
regarded as very satisfactory; more frequently the product from 100
kilograms of sulphur does not exceed 280 or 290 kilograms.
_Purif._ Commercial sulphuric acid frequently contains nitrous acid and
other oxides of nitrogen, arsenic, lead, and saline matter. The nitrous
acid may be removed by adding a little sulphate of ammonia, and heating
the acid to ebullition for a few minutes. Both nitric and nitrous acid are
thus entirely decomposed into water and nitrogen gas. The arsenic may be
got rid of by adding a little sulphide of barium to the acid, agitating
the mixture well, and, after repose, decanting and distilling it. Lead,
which exists as sulphate, may be separated as a white precipitate by
simply diluting the acid with water. Saline matter may be removed by
simple rectification. A good way of purifying oil of vitriol is to heat it
nearly to the boiling point, and pass a current of hydrochloric acid
through it; the arsenic is thus carried over as the volatile chloride of
arsenic, while the nitrous and nitric acids are expelled almost
completely. To obtain a perfectly pure acid, it should be distilled after
the removal of the nitrous acid and arsenic by the methods indicated
above. “The distillation is most conveniently conducted, on the small
scale, in a glass retort, containing a few platinum chips, and heated by a
sand bath or gas-flame, rejecting the first 1/2 fl. oz. that comes over.”
(Ph. E.) In the Ph. D. the first tenth of the distillate is ordered to be
rejected, and the process to be stopped when no more than about 1 fl. oz.
is left in the retort.
According to Dr Ure, the capacity of the retort should be from 4 to 8
times as great as the volume of the acid, and connected with a large
tubular receiver by a loosely fitting glass tube, 4 feet long and 1 to 2
inches in diameter. “The receiver should not be surrounded with cold
water.” We find that fragments of glass, or of rock crystals, may be
advantageously substituted for platinum foil, to lessen the explosive
violence of the ebullition. Sulphuric acid which has become brown by
exposure may be decolorised by heating it gently, the carbon of the
organic substances being thus converted into carbonic acid.
_Prop._ Commercial sulphuric acid (oil of vitriol) is a colourless,
odourless, and highly corrosive liquid, the general properties of which
are well known. Its sp. gr. at 60° should never be greater than 1·848, or
less than 1·840. (Miller and Odling give the sp. gr. of the pure and
concentrated acid as 1·842; Abel and Bloxam, as 1·848; Apjohn gives it as
1·846, and Hardwich about 1·845.) It is immediately coloured by contact
with organic matter. It attracts water so rapidly from the atmosphere when
freely exposed to it, as to absorb 1-3rd of its weight in 24 hours, and 6
times its weight in a few months. When 3 volumes are suddenly mixed with 2
of water, the temperature of the mixture rises more than 180° Fahr. Its
freezing point appears to be about 60° below that of water (Miller and
Odling give that of the rectified acid as -30° Fahr.; Apjohn and Abel and
Bloxam, -29°). It boils at about 620° Fahr. (620·6°, Odling; 620°,
Hardwich and Fownes; 617°, Apjohn; 590·6°, Abel and Bloxam). It exhibits
all the properties of the acids in an exalted degree. Its salts are called
sulphates.
In the following table is given the quantity of anhydrous sulphuric acid
contained in sulphuric acid at 60°F. (15·5°C.).
+--------------------------------+----------------------------------+
|Hydrated Sp. Gr. Anhydrous | Hydrated Sp. Gr. Anhydrous |
|Sulphuric Acid. | Sulphuric Acid. |
|Acid. | Acid. |
| | |
| 100 1·8485 81·54 | 76 1·6630 61·97 |
| 99 1·8475 80·72 | 75 1·6520 61·15 |
| 98 1·8460 79·90 | 74 1·6415 60·34 |
| 97 1·8439 79·09 | 73 1·6321 59·55 |
| 96 1·8410 78·28 | 72 1·6204 58·71 |
| 95 1·8376 77·40 | 71 1·6090 57·89 |
| 94 1·8336 76·65 | 70 1·5975 57·08 |
| 93 1·8290 75·83 | 69 1·5868 56·26 |
| 92 1·8233 75·02 | 68 1·5760 55·45 |
| 91 1·8179 74·20 | 67 1·5648 54·63 |
| 90 1·8115 73·39 | 66 1·5503 53·82 |
| 89 1·8043 72·57 | 65 1·5390 53·00 |
| 88 1·7962 71·75 | 64 1·5280 52·18 |
| 87 1·7870 70·94 | 63 1·5170 51·37 |
| 86 1·7774 70·12 | 62 1·5066 50·55 |
| 85 1·7673 69·31 | 61 1·4960 49·74 |
| 84 1·7570 68·49 | 60 1·4860 48·92 |
| 83 1·7465 67·68 | 59 1·4760 48·11 |
| 82 1·7360 66·86 | 58 1·4660 47·29 |
| 81 1·7245 66·05 | 57 1·4560 46·58 |
| 80 1·7120 65·23 | 56 1·4460 45·68 |
| 79 1·6993 64·42 | 55 1·4360 44·85 |
| 78 1·6870 63·60 | 54 1·4265 45·03 |
| 77 1·6750 62·78 | 53 1·4170 43·22 |
+--------------------------------+----------------------------------+
_Pur._ “Free from colour and odour. Sp. gr. 1·843. 100 gr. are saturated
by 285 gr. of crystallised carbonate of soda.” (Ph. L.) “What remains
after the acid is distilled to dryness does not exceed 1/400th part of its
weight. Diluted sulphuric acid is not discoloured by sulphuretted
hydrogen.” (Ph. L. 1836.) “Diluted with its own volume of water, only a
scanty muddiness arises, and no orange fumes escape. Sp. gr. 1·840.” (Ph.
E.) “The rectified acid (ACIDUM SULPHURICUM PURUM——Ph. E. & D.) is
colourless; dilution causes no muddiness; solution of sulphate of iron
shows no reddening at the line of contact when poured over it. Sp. gr.
1·845.” (Ph. E.) Sp. gr. 1·846——Ph. D.; 1·843——B. P.; 1·842——Ure.
_Tests._——See SULPHATE.
_Uses, &c._ “The uses of sulphuric acid are so numerous that it would be
impossible to mention all of them, sulphuric acid being to chemical
industry what iron is to the mechanical. Sulphuric acid is employed in
preparing a great many other acids——among them, nitric, hydrochloric,
sulphurous, carbonic, tartaric, citric, phosphoric, stearic, oleic, and
palmitic. Further, sulphuric acid is used in making superphosphates, soda,
sulphate of ammonia, alum, sulphates of copper and iron, in paraffin and
petroleum refining, silver refining, manufacture of garacine, garanceux,
and other madder preparations, manufacture of glucose from starch, to
dissolve indigo, &c.[216] In the diluted state it is used in medicine.
When swallowed, it acts as a violent corrosive poison. The antidotes are
chalk, whiting, magnesia, carbonate of soda, or carbonate of potash, mixed
with water, or any bland diluent, and taken freely, an emetic being also
administered.
[Footnote 216: Wagner.]
_Estim._ The strength of sulphuric acid is most correctly ascertained by
its power of saturating bases. In commerce, it is usually determined from
its sp. gr. The quantity of sulphuric acid present in a compound may be
determined by weighing it under the form of sulphate, as explained in a
former part of this volume. See ACIDIMETRY.
_Concluding Remarks._ According to most of our standard works on
chemistry, British oil of vitriol, when purified and brought to its
maximum strength by distillation, is a definite chemical compound, having
the formula H_{2}SO_{4}, and designated normal sulphuric acid by Odling.
Marignac, however, asserts that the distilled acid always contains an
excess of water, and that the true monohydrate can only be obtained by
submitting fuming sulphuric acid (‘Nordhausen s. a,’) to congelation.
According to this chemist, the true monohydrate readily freezes in cold
weather, and remains solid up to 51° Fahr. Two other definite hydrates of
sulphuric acid are generally recognised by chemists, viz.——Bihydrated
sulphuric acid (‘glacial s. a,’), having a sp. gr. of 1·78; freezing at
about 40° Fahr. (47°, Miller); and boiling at about 435° (Apjohn; 401° to
410°, Odling): Terhydrated sulphuric acid, having a sp. gr. of 1·632, and
the boiling-point 348° Fahr. See also SULPHURIC ACID, NORDHAUSEN
(_below_).
=Sulphuric Acid, Al′coholised.= _Syn._ ACIDUM SULPHURICUM ALCOHOLISATUM,
L.; EAU DE RABEL, Fr. _Prep._ (P. Cod.) To rectified spirit, 3 parts, add,
very gradually, sulphuric acid, 1 part. It is generally coloured by
letting it stand over a little cochineal. Refrigerent, and, externally,
escharotic.——_Dose_, 1/2 fl. dr. to water, 1 pint; as a cooling drink in
fevers, &c.
=Sulphuric Acid, Anhy′drous.= SO_{3}. _Syn._ SULPHURIC ANHYDRIDE, DRY
SULPHURIC ACID; ACIDUM SULPHURICUM SINE AQUÂ, L. _Prep._ 1. By heating
Nordhausen acid to about 100° Fahr. in a glass retort connected with a
well-cooled receiver.
2. By distilling anhydrous bisulphate of soda, which has previously been
raised to a low red heat in an earthen retort, to which a receiver is
fitted without the aid of corks.
3. (Barreswill.) 2 parts of the strongest oil of vitriol are gradually
added to 3 parts of anhydrous phosphoric acid, contained in a retort
surrounded by a freezing mixture; when the compound has assumed a brown
colour, the retort is removed from the bath, and connected with a receiver
which is set there in its place; a gentle heat is now applied to it, when
white vapours pass over into the receiver, and condense there under the
form of beautiful silky crystals. The product equals in weight that of the
phosphorus originally employed. “If a few drops of water be added, a
dangerous explosion ensues.”
_Prop._ White, silky, asbestos-like crystals, deliquescing rapidly, and
fuming in the air; put into water, it hisses like a red-hot iron; it melts
at 77°, and rapidly volatilises at 86° Fahr.; it does not redden dry
litmus paper; sp. gr. 1·97 at 78° Fahr.
=Sulphuric Acid, Aromat′ic.= _Syn._ ELIXIR OF VITRIOL, ACID E. OF V.;
ACIDUM SULPHURICUM AROMATICUM (B. P., Ph. E. & D.), L. _Prep._ 1. (Ph. E.
& D.) Oil of vitriol, 3-1/2 fl. oz.; rectified spirit, 1-1/2 pint; mix,
add of powdered cinnamon, 1-1/2 oz.; powdered ginger, 1 oz.; digest for 6
days (7 days——Ph. D.), and filter. Sp. gr. ·974——Ph. D.
2. (Wholesale.) From compound tincture of cinnamon, 1 gall.; oil of
vitriol, 1 lb.; mix, and in a week filter——_Dose_, 10 to 30 drops, in the
same case as the dilute acid.
3. (B. P.) Sulphuric acid, 3; rectified spirit, 40; cinnamon, in powder,
2; ginger, in powder, 1-1/4; mix the acid gradually with the spirit, add
the powders, macerate for 7 days, and filter.——_Dose_, 5 to 30 minims.
=Sulphuric Acid, Dilute′.= _Syn._ SPIRIT OF VITRIOL; ACIDUM SULPHURICUM
DILUTUM (B. P., Ph. L., E., & D.), L. _Prep._ 1. (Ph. L.) Take of
sulphuric acid, 15 fl. dr., and dilute it gradually with distilled water,
q. s. to make the whole exactly measure a pint. Sp. gr. 1·103. “1 fl. oz.
of this acid is exactly saturated by 216 gr. of crystallised carbonate of
soda.”
2. (Ph. E.) Sulphuric acid, 1 fl. oz.; water, 13 fl. oz. Sp. gr. 1·090.
3. (Ph. D.) Pure sulphuric acid, 1 fl. oz.; distilled water, 13 oz. Sp.
gr. 1·084.
4. (B. P.) Sulphuric acid, 3; distilled water, q. s. to measure 35-3/4;
mix by adding the acid gradually to the water.——_Dose_, 4 to 20 minims.
_Prop., &c._ Antiseptic, tonic, and refrigerant.——_Dose_, 10 to 30 drops,
largely diluted with water, several times daily; in low typhoid fevers,
passive hæmorrhages, profuse perspiration, in various skin diseases to
relieve the itching, in dyspepsia, &c. It is also used externally.
=Sulphuric Acid, Nordhausen.= _Syn._ FUMING SULPHURIC ACID; ACIDUM
SULPHURICUM FUMANS, L. _Prep._ By distilling calcined ferrous sulphate
(‘green vitriol’) in earthen retorts. The retorts, which are shown at A in
the plate after the ‘green vitriol’ has been put into them, are placed in
a galley-furnace, as shown below, the necks passing through the wall of
the furnace, and being properly secured to the necks of the receivers (B
B.). Into each of the flasks 2-1/2 lbs. of green vitriol are put; on the
first application of heat only sulphurous acid and weak hydrated sulphuric
acid come over, and are usually allowed to escape, the receivers not being
securely luted until white vapours of anhydrous sulphuric acid are seen.
Into each of the receiving flasks 30 grams of water are poured, and the
distillation continued for 24 to 36 hours. The retort flasks are then
again filled with raw material, and the operation repeated four times
before the oil of vitriol is deemed strong enough. The residue in the
retorts is red (peroxide) of iron, still retaining some sulphuric acid.
The product is a brown oily liquid, which fumes in the air, is intensely
corrosive, and has a sp. gr. about 1·900. When heated to about 100° Fahr.
the anhydrous acid is given off, and ordinary oil of vitriol is left.
According to Marignac, crystals of normal sulphuric acid (H_{2}SO_{4}) are
formed in this acid when it is submitted to a low temperature. Nordhausen
acid is so called from the place of its manufacture in Saxony. It may be
regarded as a mixture or compound of H_{2}SO_{4} and SO_{2}. It is chiefly
used for dissolving indigo.
[Illustration]
=SULPHURIC ANHYDRIDE.= See SULPHURIC ACID, ANHYDROUS.
=SULPHURIC E′THER.= See ETHER.
=SUL′PHUROUS ACID.= SO_{2}. _Syn._ SULPHURUS ANHYDRIDE; ACIDUM
SULPHUROSUM, B. P. This compound is freely evolved in the gaseous form
when sulphur is burnt in air or oxygen, and when the metals are digested
in hot sulphuric acid; and, mixed with carbonic acid, when charcoal, chips
of wood, cork, and sawdust, are treated in the same way.
_Prep._ 1. By heating together sulphur and strong sulphuric acid.
2. By the action of sulphuric acid on chippings of copper or mercury at a
gentle heat. Pure.
3. (Berthier.) By heating, in a glass retort, a mixture of black oxide of
manganese, 100 parts, and sulphur, 12 or 14 parts. Pure. The gas evolved
should be collected over mercury, or received into water.
4. (Redwood.) Pounded charcoal, 1/2 oz.; oil of vitriol, 4 fl. oz.; mix in
a retort, apply the heat of a spirit lamp, and conduct the evolved gases
by means of a bent tube into a bottle containing water. The sulphurous
acid is absorbed, whilst the carbonic acid gas passes off.
5. (B. P.) Distilled water, saturated with sulphurous anhydride. It is
colourless and emits a pungent odour. Used as a deoxidiser, disinfectant,
and antiseptic. Diluted with from 1 to 2 parts of water it is employed as
a lotion for wounds, cuts, ulcers, bed-sores, scalds, and burns; with from
1 to 5 of water it is used as a gargle, also as a lotion in parasitic skin
diseases; from 1/2 to 1 dr., in a wine-glassful of water, 3 times a day,
relieves constant sickness.
_Prop., &c._ Water absorbs 30 times its volume of this gas. Pure liquid
sulphurous acid can only be obtained by passing the pure dry gas through a
glass tube surrounded by a powerful freezing mixture. Its sp. gr. is 1·45;
boiling point, 14° Fahr.; it causes intense cold by its evaporation.
Sulphurous acid forms salts called sulphites.
_Uses._ To bleach silks, woollens, straw, &c., and to remove vegetable
stains and iron-moulds from linen. For these purposes it is prepared from
sawdust or any other refuse carbonaceous matter.
Several preparations containing sulphurous acid have recently been
invented by the Editor and introduced to the public as agents in
sanitation under the name of _Sporokton_ (germ-killer). To understand the
nature and merits of these preparations it is desirable to explain the
true and individual meanings of ‘Deodoriser,’ ‘Antiseptic,’ and
‘Disinfectant,’——words which are too often improperly employed as if they
had the same signification, and as if, in fact, they were convertible
terms.
A deodoriser is a substance which will absorb or destroy bad smells; an
antiseptic is an agent which will prevent or retard putrefaction; and a
disinfectant is an agent which will render harmless the virus of smallpox,
scarlet fever, measles, diphtheria, influenza, pleuro-pneumonia, cattle
plague, glanders, distemper in dogs, and other infectious or contagious
diseases.
Now, medical authorities and sanitarians are of opinion that the most
potent disinfectant with which we are acquainted is sulphurous acid, a gas
which has been used for ages, as a fumigator. Sulphurous acid has not,
however, been so generally employed for disinfecting purposes as one might
from these circumstances have expected, on account of the difficulties
and inconveniences which formerly attended its generation.
To remove these drawbacks, and to render sulphurous acid, both as a gas
and in solution, easily and cheaply available for the above-named and many
other applications, sporokton has been invented. Several varieties are
made; they are as follows:
_Liquid No. 1._——This preparation consists of a colourless solution of a
non-volatile antiseptic, usually a salt of zinc, impregnated with eighty
times its bulk of sulphurous acid gas; in other words, one pint of the
liquid contains ten gallons of gas. Liquid sporokton is, in fact, a
combination of one of the most powerful antiseptics with the disinfectant;
the former ingredient will effectually prevent the putrefaction of any
solid or liquid animal or vegetable matter with which it may come in
contact, while the sulphurous acid will rapidly pass off in the gaseous
state into the surrounding air and act as an energetic destroyer of
noxious atmospheric impurities.
Liquid sporokton absorbs ammonia and sulphuretted hydrogen, destroys bad
smells, and prevents the spread of infectious diseases; it is,
consequently, a valuable agent for the deodorisation and disinfection of
wards of hospitals, sick rooms, dairies, larders, ship, stables,
cow-houses, kennels, piggeries, slaughter-houses, urinals, water-closets,
privies, cesspools, sewers, drains, and other similar buildings and
places.
After it has parted with the whole of its sulphurous acid gas, liquid
sporokton leaves an odourless, non-volatile antiseptic and absorber of
ammonia and sulphuretted hydrogen.
Liquid sporokton evolves its sulphurous acid by simple exposure to air,
without the aid of heat, so that no risk of fire attends its use, as is
the case when rooms, buildings, holds of ships, &c., are fumigated with
this gas by the old plan; it will not stain or in any other way injure
undyed woollen, linen, or cotton goods. It is consequently well adapted
for the disinfection of underclothing, sheets, blankets, bed-furniture,
&c.
Liquid sporokton may be employed for the instantaneous preparation of a
bath or lotion of sulphurous acid, to be used, under medical direction, in
the treatment of itch, ringworm, chronic eczema, lepra, psoriasis,
impetigo, pityriasis, &c., in man, as well as mange, scab, and other skin
affections in the lower animals.
Liquid sporokton is clean, it requires no skill in using it, and its
action is perfectly controllable.
_Liquid, No. 2._——This preparation is specially made for the disinfection
and purification of old beer barrels, wine casks, and the like. It is
similar in composition to, and may be used for the same purpose as No. 1;
except, however, that as No. 2, unlike No. 1, is liable, from its
containing iron instead of zinc, to stain linen, wood, &c., it should not
be employed for disinfecting clothing or sprinkling over floors, decks of
ships, and the like.
_Solid._——This is a powder, usually a mixture of calcium sulphite and
ferric chloride, which, by simple expose to air, will slowly and steadily,
or when sprinkled with water, rapidly give out 25 per cent. of its weight
of sulphurous acid and leave no unpleasant smell behind it.
Sulphurous acid gas, unlike non-volatile disinfectants, quickly mingles
with the air, and seeks out, as it were, the noxious atmospheric
impurities it is capable of destroying.
Solid sporokton, in addition to evolving sulphurous acid, contains an
excess of ferric chloride which, together with this gas, renders it a most
useful and efficient antiseptic.
=Sulphurous Anhydride.= See SULPHUROUS ACID.
=SU′MACH.= This dye stuff is chiefly used as a substitute for galls. With
a mordant of acetate of iron, it gives grey or black; with tin or acetate
of alumina, yellow; and with sulphate of zinc, a yellowish-brown; alone,
it gives a greenish-fawn colour.
=SUM′BUL.= _Syn._ MUSK ROOT, JATAMANSI, SUMBUL ROOT; SUMBUL RADIX (B. P.).
A substance introduced to British medicine by Dr A. B. Granville, in 1850.
It occurs in circular pieces, varying from 1 to 3 or 4 inches in diameter;
has a musk-like odour, and a sweet balsamic taste. It acts as a powerful
stimulant, especially of the nervous system. In India and Persia it has
long been used as a medicine, a perfume, and as incense.——_Dose_, 15 gr.
to 1 dr., either masticated, or made into an infusion, electuary, or
tincture; in cholera, hysteria, neuralgia, epilepsy, low fevers, and
various other spasmodic and nervous disorders.
=SUMMER DRINKS.= See LEMONADE, SHERBET, &c.
=SU′PER-.= See NOMENCLATURE.
=SUP′PER.= The evening meal; the last meal of the day. Supper is generally
an unnecessary meal, and, when either heavy, or taken at a period not long
before that of retiring to rest, proves nearly always injurious,
preventing sound and refreshing sleep, and occasioning unpleasant dreams,
nightmare, biliousness, and all the worst symptoms of imperfect digestion.
The last meal of the day should be taken at least three hours before
bedtime. Even when it consists of some ‘trifle,’ as a sandwich or biscuit,
an interval of at least an hour should elapse before retiring to rest. In
this way restlessness and unpleasant dreams will become rare.
=SUPPOS′ITORY.= _Syn._ SUPPOSITORIUM, L. A medicine placed in the rectum
for the purpose of affecting the lower intestine, or, by absorption, the
system generally. Suppositories are rounded, usually elongated masses,
having the active medicine combined with some substance which will retain
the proper shape, as soap, spermaceti cerate, or cacao-butter. The latter
substance is, perhaps, the best vehicle for remedies prescribed in this
form. It is, however, rather too soft to be used without admixture.
According to Dorvault, the addition of one eighth part by weight of wax
imparts the proper hardness.
All difficulty of removing suppositories from the mould may be obviated by
having the moulds previously dusted with lycopodium.
The mode of proportioning the doses of active ingredients has been noticed
in the article ENEMA.
=Suppository, Astringent.= _Syn._ SUPPOSITORIUM ASTRINGENS (Reuss).
_Prep._ Powdered oak bark, 2 dr.; tormentil, 2 dr.; honey, q. s. For 8
suppositories.
=Suppository of Carbolic Acid.= _Syn._ SUPPOSITORIUM ACIDI CARBOLICI (Ph.
U. S.). _Prep._ Carbolic acid, 12 gr.; oil of theobroma, 348 gr.; water,
q. s. Dissolve the acid in a few drops of water, and mix it with 1 dr. of
oil of theobroma; then add it to the remainder of the theobroma previously
melted, and cooled to the temperature of 95° F., and pour the whole
immediately into moulds of 30 gr. each, standing in iced water.
=Suppository of Copaiba.= _Syn._ SUPPOSITORIUM COPAIBA (Colombat). _Prep._
Solidified copaiba, 1 dr.; butter of cacao, 1 dr.; extract of opium, 1/2
gr.
=Suppository of Elaterium.= _Syn._ SUPPOSITORIUM ELATERII (St B. H.).
_Prep._ Extract of elaterium, 2 gr.; hard soap, 10 gr.; water, q. s. Mix.
=Suppository, Emollient.= _Syn._ SUPPOSITORIUM EMOLLIENS. _Prep._ Butter
of cacao and spermaceti in equal parts; melted together.
=Suppository of Iodide of Potassium.= _Syn._ SUPPOSITORIUM POTASSII
IODIDII (Mr Stafford). _Prep._ Iodide of potassium, 1 gr. to 4 gr.;
extract of henbane, 6 gr.; extract of hemlock, 6 gr. In enlarged prostate.
=Suppository, Irritant.= _Syn._ SUPPOSITORIUM IRRITANS (Richard). _Prep._
Butter of cacao, 2 dr.; aloes, 4 gr.; tartarised antimony, 1 gr. To
restore the hæmorrhoidal flux.
=Suppository of Lead (Compound).= _Syn._ SUPPOSITORIUM PLUMBI COMPOSITUM
(B. P.). _Prep._ Acetate of lead, in powder, 36; opium, in powder, 12;
benzoated lard, 42; white wax, 10; oil of theobroma, 80; melt the wax and
oil of theobroma with a gentle heat, then add the other ingredients,
previously rubbed together in a mortar, and, having mixed them thoroughly,
pour the mixture while it is fluid into suitable moulds of the capacity of
15 gr. The above makes 12 suppositories.
=Suppository of Mercury.= _Syn._ SUPPOSITORIUM HYDRARGYRI (B. P.). _Prep._
Ointment of mercury, 60 gr.; benzoated lard, 20 gr.; white wax, 20 gr.;
oil of theobroma, 80 gr.; melt all but the mercurial ointment together,
then add the ointment of mercury, stir till well mixed, and immediately
pour into moulds of the capacity of 15 gr. The above makes 12
suppositories.
=Suppository of Morphia.= _Syn._ SUPPOSITORIUM MORPHIÆ (B. P.). _Prep._
Hydrochlorate of morphia, 6 gr.; oil of theobroma, 90 gr.; benzoated lard,
64 gr.; white wax, 20 gr.; melt the wax and oil of theobroma with a gentle
heat, then add the hydrochlorate of morphia and benzoated lard, previously
rubbed together in a mortar, and mix all the ingredients thoroughly; pour
the mixture, while it is fluid, into suitable moulds of the capacity of 15
gr., or the fluid mixture may be allowed to cool, and then be divided into
12 equal parts, each of which should be made into a conical form.
=Suppository of Opium.= _Syn._ SUPPOSITORIUM OPII (Ph. U. S.). _Prep._
Extract of opium, 12 gr.; oil of theobroma, 348 gr.; water, q. s. Proceed
as for carbolic acid suppository.
=Suppository for Piles.= _Syn._ SUPPOSITORIUM HÆMORRHOIDALE, S. SEDATIVUM,
L. _Prep._ 1. Powdered opium, 2 gr.; finely powdered galls, 10 gr.;
spermaceti cerate, 1 dr.
2. (Ellis.) Powdered opium, 2 gr.; soap, 10 gr.; mix.
3. (Richard.) Extracts of opium and stramonium, of each 1 gr.;
cacao-butter, 2 dr. Used when the piles are very painful.
=Suppository, Pur′gative.= _Syn._ SUPPOSITORIUM CATHARTICUM, L. _Prep._ 1.
Soap, 1 dr.; elaterium, 1 to 2 gr.; mix. As a strong purge.
2. (Niemann.) Soap, 2 dr.; common salt, 1 dr.; honey, q. s.; mix. As a
mild cathartic.
=Suppository of Quinine.= _Syn._ SUPPOSITORIUM QUINÆ (Boudin). _Prep._
Sulphate of quinine, 15 gr.; butter of cacao, 1-1/2 dr. Mix.
=Suppository, Resol′vent.= _Syn._ SUPPOSITORIUM RESOLVENS, L. _Prep._
(Stafford.) Iodide of potassium, 3 to 4 gr.; extracts of henbane and
hemlock, of each 6 gr. In enlargement or induration of the prostate gland.
=Suppository of Rhatany.= _Syn._ SUPPOSITORIUM RHATANIÆ (P. Cod). _Prep._
Butter of cacao, 1 dr.; extract of rhatany, 15 gr., for 1 suppository.
=Suppository, Sed′ative.= See _above_.
=Suppository of Sulphate of Soda.= _Syn._ SUPPOSITORIUM SODÆ SULPHATIS
(Phœbus). _Prep._ Dried sulphate of soda, 2 dr.; powdered soap, 4 dr.;
honey, q. s. For 4 suppositories. To be smeared over with oil when
applied.
=Suppository of Tannic Acid.= _Syn._ SUPPOSITORIUM ACIDI TANNICI (B. P.).
_Prep._ Tannic acid, 36 gr.; benzoated lard, 44 gr.; white wax, 10 gr.;
oil of theobroma, 90 gr.; melt the wax and oil with a gentle heat, then
add the tannic acid and benzoated lard, previously rubbed together, and
mix thoroughly. Pour the mixture while it is fluid into suitable moulds of
the capacity of 15 gr. The above makes 12 suppositories.
=Suppository, Ver′mifuge.= _Syn._ SUPPOSITORIUM ANTHELMINTICUM, S.
VERMIFUGUM, L. _Prep._ (Swediaur.) Aloes, 4 dr.; common salt, 3 dr.;
flour, 2 dr.; honey, q. s. to make a stiff mass; divide into proper-shaped
pieces, weighing about 15 gr. each. One to be used after each motion.
=Suppositories of Aloes.= _Syn._ SUPPOSITORIA ALOES (B. P.). _Prep._ Aloes
in fine powder. 1 dr.; oil of theobroma, 300 gr. Proceed as for carbolic
acid suppository, omitting the water.
=Suppositories of Assafœtida.= _Syn._ SUPPOSITORIA ASSAFŒTIDÆ (Ph. U. S.).
_Prep._ Tincture of assafœtida, 1 oz.; oil of theobroma, 320 gr. Let the
tincture evaporate by exposure to the air until of the consistence of a
thick syrup, and proceed as for suppositories of carbolic acid.
=Suppositories of Belladonna.= _Syn._ SUPPOSITORIA BELLADONNÆ (Ph. U. S.).
_Prep._ Alcoholic extract of belladonna, 6 gr.; oil of theobroma, 354 gr.
Proceed as for carbolic acid suppositories.
=Suppositories of Carbolic Acid with Soap.= _Syn._ SUPPOSITORIA ACIDI
CARBOLICI CUM SAPONE (B. P.). _Prep._ Carbolic acid, 12 gr.; curd soap, in
powder, 180 gr.; starch, q. s.; mix the carbolic acid with the soap, and
add starch, q. s., to make of a suitable consistency; divide into 12 equal
parts, and make each suppository into a conical or other convenient form.
=Suppositories of Colocynth.= _Syn._ SUPPOSITORIA COLOCYNTHIDIS (Sp. Ph.).
_Prep._ Colocynth, 30 gr.; salt, 1 dr. Evaporate to a due consistence.
=Suppositories of Morphia with Soap.= _Syn._ SUPPOSITORIA MORPHIÆ CUM
SAPONE (B. P.). _Prep._ Hydrochlorate of morphia, 6 gr.; glycerin of
starch, 50 gr.; curd soap in powder, 100 gr.; starch, q. s. Mix the
hydrochlorate with the glycerin of starch and soap, and add starch q. s.
to form a paste of suitable consistence. Divide into 12 equal parts, each
of which is to be made into a conical or other convenient form of
suppository.
=Suppositories of Tannic Acid with Soap.= _Syn._ SUPPOSITORIA ACIDI
TANNICI CUM SAPONE (B. P.). _Prep._ Tannic acid, 36 gr.; glycerin of
starch, 50 gr.; curd soap in powder, 100 gr.; starch, q. s. Mix the tannic
acid with the glycerin of starch and soap, and add starch q. s. to form a
paste of suitable consistence, divide into 12 equal parts, each of which
is to be made into a conical or other convenient form of suppository.
=Suppositories, Vaginal.= _Syn._ SUPPOSITORIA VAGINALE (Guadrist). _Prep._
Liquid chloride of zinc, 5 minims; sulphate of morphia, 1/2 gr.; mix with
2 dr. of the following paste:——Thick mucilage of tragacanth, 6 parts;
white sugar, 3 parts; starch, 9 parts. Mr Druitt prescribes in
leucorrhœa:——Tannin, 10 gr., with mucilage of tragacanth, q. s.
=SURGERY.= “This word,” says Brande, “in its modern acceptation, may be
defined as the practical application of science, in the use of all
mechanical and instrumental means, for the removal of diseases and the
relief of human suffering.”
One of the earliest professors of the ancient art of surgery, of whom
history affords a reliable record, was Hippocrates, a Greek, who lived in
the fifth century of our era, and who seems to have been a man of
considerable skill for the period in which he flourished, since he could
set fractures, reduce dislocations, and perform other important
operations. About two centuries after Hippocrates the studies of surgery,
anatomy, and medicine were prosecuted with evident success at Alexandria.
The Alexandrian school produced some able surgeons, one of whom, Ammianus,
invented an instrument for crushing the stone in the bladder, and was thus
the first to practise the now important surgical operation known as
lithotrity. At the beginning of the Christian era Celsus practised the art
of surgery in Rome; he appears to have been the first to operate for
cataract, and to apply ligatures to arteries after operations. It is
curious to note that so practical a people as the Romans held the art of
surgery in comparative contempt, and banished its professors, whose
services they discarded, for the practice of spells, incantations, and
charms.
In the sixth century lived Œtius, who conceived the idea of dissolving
urinary calculi by the administration of internal remedies; and in the
tenth, Avicenna, who, it has been conjectured, invented the flexible
catheter, and was the inventor of the instrument now known as Hey’s saw.
In 1271 the Paris College of Surgeons was founded, and the College of
Surgeons of London in 1460, and the Edinburgh College in 1505.
The most prominent figure in the annals of surgery of the 16th century was
Paré, a man of great originality of thought, whose works exercised a
considerable influence over his own contemporaries, and for many years
subsequently. Towards the end of the 17th century lived Wiseman, serjeant
surgeon to Charles II. Wiseman was a man of considerable ability, and was
the first to demonstrate that gun-shot wounds were not of a poisonous
nature; and that therefore the old practice of applying painful and
caustic dressings to them might most advantageously be abandoned. A
contemporary of Wiseman was Young, of Plymouth, who merits notice as
being the first who performed the flap-operation in amputation.
In the 17th century also lived Frère St Cosme, a French monk, who obtained
considerable fame as an operator for lithotomy, for the performance of
which he regarded himself as especially chosen by Heaven. In the 18th
century lived in England Cheselden and Douglas, two eminent lithotomists;
John Hunter, Pott and Ley; in Scotland, Benjamin and John Bell and Monro;
and in Ireland, O’Halloran and Deases; whilst in France flourished Petit,
celebrated for his treatise on diseases of the bones; from Germany,
Rechter and Haller.
In this century (1784) was founded the Royal College of Surgeons in
Ireland. In the present century there are few branches of science in which
greater progress has been made than that of surgery. From amongst the most
eminent of the English surgeons of the present century we may select the
following names:——Abernethy, Blizard, Astley Cooper, Brodie, Dalrymple,
Guthrie, Aston Key, Liston, Stanley, Travers, Arnott, Bowman, Erichsen,
Fergusson, Prescott Hewett, Hilton, Lane, Lawrence, Paget, Spencer Wells,
Marshall, Christopher Heath, Durham, Bryant, Nunn, Lee, H. Smith, Mason,
and Pollock.
=SUSPENDED ANIMATION.= See ASPHYXIA.
=SWAL′LOW.= Three or four species of _hirundo_ (Linn.) pass under this
name. It was once held in great repute in medicine. Even the excrement was
included among the simples of the Ph. L. 1618. The swallow is an
insectivorous bird, but, like the sparrow and rook, is much persecuted for
its good services. It has been calculated that, directly and indirectly, a
single swallow is the humble means of lessening the race of one kind of
insect alone to the extent of 560,970,489,000,000,000 of its race in one
year.
=SWEEPING.= Before commencing to sweep, the floor should be strewed with a
good amount of damp tea-leaves, saved for the purpose; these collect the
dust and thereby save the furniture, which as far as practicable should be
covered up during the process. Tea-leaves may also be advantageously used
upon druggets and short-piled carpets. Light sweeping and soft brooms are
desirable if these latter are to be operated upon. Many a carpet is
prematurely worn out by over-violent sweeping.
In sweeping thick-piled carpets, such as Axminster and Turkey carpets, the
servant should always be instructed to brush the way of the pile; by
following this advice the carpets may be kept clean for years; but if the
broom is used in a contrary direction, all the dust will be forced into
the carpet, and soon spoil it.
=SWEET BALLS.= _Prep._ Take of Florentine orris root, 3 oz.; cassia, 1
oz.; cloves, rhodium wood, and lavender flowers, of each 1/2 oz.;
ambergris and musk, of each 6 gr.; oil of verbena, 10 or 12 drops; beat
them to a paste, form this into balls with mucilage of gum tragacanth
made with rose water, pierce them, whilst soft, with a needle, and, when
they are quite dry and hard, polish them. Worn in the pocket as a perfume.
Some persons varnish them, but that keeps in the smell.