Nitrogenous matter 12·96
Starch 66·43
Dextrin 10·00
Fatty matter 2·76
Cellulose 4·75
Mineral matter 3·10
------
100·00
According to Dr Ure, the sp. gr. of ENGLISH BARLEY is 1·25 to 1·33
(average, 1·235), and the weight of the husk is about 1-6th; that of BIGG,
1·227 to 1·265, and weight of husk, 2-9ths.
The analyses of the following varieties of barley, gave as the composition
of the ashes of the grains:--
---------------------------------------------------
|Unknown |Chevalier| From |Chevalier
| | Barley |Moldavia| Barley
-------------+--------+---------+--------+---------
Potash | 21·14 | 20·77 | 37·55 | 7·70
Soda | | 4·56 | 1·06 | 0·36
Lime | 1·65 | 1·48 | 1·21 | 10·36
Magnesia | 7·26 | 7·45 | 10·17 | 1·26
Sesquioxide | | | |
of iron | 2·13 | 0·51 | 1·02 | 1·46
Sulphuric | | | |
acid | 1·91 | 0·79 | 0·27 | 2·99
Silica | 30·68 | 32·73 | 24·56 | 70·77
Phosphoric | | | |
acid | 28·53 | 31·69 | 38·64 | 1·99
Chloride of | | | |
Sodium | 1·10 | | 1·47 | 1·10
---------------------------------------------------
In the 'Journal of the Agricultural Society' for 1873 is a report by
Messrs Lawes and Gilbert of twenty years' experiments with barley. The
soil of a field at Rothampstead, in which the barley had been grown for
twenty years, consisted of heavy loam, with a subsoil of clay resting on
chalk, and was previous to the barley being planted almost exhausted by
cropping. The produce was found to be greatest during the absence of
drought and sudden alterations of temperature, the rather cool but uniform
season of 1854 giving the heaviest crops. The yield from farm-yard manure
and nitrate of soda was found in dry seasons to be rather larger than that
from ammonia salts. Barley manured with phosphates was found to ripen one
to two weeks earlier than when the phosphate was omitted.
The average produce per acre of a few of the principal plots is given
below. The "ammonium salts" are stated to be a mixture of equal parts of
sulphate and chloride; the "alkali salts" consist of the sulphates of
potassium, sodium, and magnesium; the "cinerials" consist of alkali salts,
plus superphosphate:
KEY:
A: Dressed Corn.
B: Straw and Chaff.
C: Total Produce.
D: Corn to 100 Straw.
E: Weight per Bushel of Dressed Corn.
F: Produce of second 10 yrs. over or under first 10 yrs.
-----------------------------+--------+------+----+----+----+--------
Manures per Acre. | A | B | C | D | E | F
-----------------------------+--------+------+----+----+----+--------
|bushels.| cwts.|lbs.| |lbs.|per cwt.
| | | | | |
Unmanured | 20 |11-3/4|2454|86·6|52·3|- 23·6
Mixed cinerials | 27-1/2 |14-3/8|3162|96·4|53·4|- 20·2
Ammonium salts, 200 lbs. | 32-1/2 |18-1/2|3919|89·2|52·1|- 9·7
Ammonium salts, 200 lbs., and| | | | | |
alkali salts | 35 |20-3/4|4317|86·3|52·8|- 5·3
Ammonium salts, 200 lbs., and| | | | | |
superphosphate | 47 |27-5/8|5760|86·8|53·5|+ 2·7
Ammonium salts, 200 lbs., and| | | | | |
cinerials | 46-1/4 |28-1/2|5817|83·2|54·0|- ·3
Rape cake (mean 1300 lbs.) | 45-1/4 |26-7/8|5571|87·3|53·8|
Farmyard manure, 14 tons | 48-1/4 |28-1/4|5933|88·5|54·3|+ 14·8
-----------------------------+--------+------+----+----+----+--------
The authors direct attention to the results obtained by using the cinerial
manure alone, as illustrating the unsoundness of the old "mineral theory,"
according to which plants were supposed to possess a sufficient source of
nitrogen in the atmosphere. They found a greater crop yielded by barley
than wheat, when no manures were employed, as well as when cinerials were
employed, a fact which they attribute to barley being better able than
wheat to supply itself with nitrogen, notwithstanding the deeper roots of
the latter. They state that with both wheat and barley the produce is
slowly falling off under these circumstances. With ammonium salts alone,
and with nitrate of sodium alone, there is much less falling off than when
no nitrogenous manure is used. The falling off was least with the nitrate.
The nitrate gives a rather larger crop for the same amount of nitrogen
supplied, and they found this to hold when both nitrate and ammonia are
applied with cinerials. The addition of superphosphate to ammonium salts
or sodium nitrate greatly increases the produce; the further addition of
potassium, sodium, and magnesium salts they found almost without effect.
The inference was that the barley had obtained an ample supply of potash
from the natural soil, but an insufficient supply of phosphoric acid.
When ammonium salts are used alone, and the quantity of ammonia does not
exceed 50 lbs. per acre, 3·68 lbs. of ammonia will yield an average
increase of 1 bushel of corn and 63 _lbs._ of straw--total, 115 _lbs._;
the extremes in 20 years were 2·25-18·05 _lbs._ When ammonium salts are
applied with superphosphate, 2·21 _lbs._ of ammonia will produce the same
result; the extremes were 1·47-5·36 _lbs._
Silicate of sodium had been applied for eight years and a half to half the
barley plots receiving ammonia; no increase has resulted where ammonia and
superphosphate are employed; but on the other three plots an increase had
taken place, which, in the case of the plot receiving only ammonia and
alkali salts, is very considerable.
The authors think this irregular reaction seems to show that the silicate
has not produced its effect by furnishing silica to the crop, but by some
reaction upon the plant-food of the soil. The rape cake supplied much more
nitrogen than the ammonium salts, and also some phosphates and potash.
Rape cake alone gives a better return than either ammonium salts or sodium
nitrate applied alone; but when the three manures are mixed with
superphosphate, the results for equal amounts of nitrogen show the rape
cake to be decidedly inferior. From the above experiments it is inferred
that a supply of carbonaceous matter does not increase the crop of barley.
A farm-yard manure containing about 0·64 per cent. of nitrogen supplied
far more plant food than any of the other manures. On an average of
twenty years it was found that about 8 lbs. of ammonia in the form of dung
would produce a bushel of barley, with its equivalent of straw.
In all cases which were comparable it was found that barley appropriates
more of the nitrogenous manure than wheat, save with farmyard manure. A
large amount of nitrogen applied by manure is not taken up by the crop.
Experiments in the barley field proved that large residues from ammonium
salts and sodium nitrate show a small but distinct effect upon succeeding
crops, the influence extending over many years. From an examination of the
drainage waters from lands dressed with the nitrates of ammonium and
sodium, the authors conclude that ammonium salts, as well as sodium
nitrate, will be more economically applied in the spring than in the
winter. Manures containing organic nitrogen are clearly not so liable to
loss from drainage.
Experiments were made on the growth of barley after turnips, and also in
an ordinary four-course rotation. After growing turnips ten years
consecutively with purely cinerial manures, and carting off the produce,
the yield of barley was much smaller than in the experimental field, where
barley was grown after barley. The turnips, though very small crops, had
exhausted the soil of nitrogen to a greater extent than corn crops would
have done. On one plot where rape cake had been applied to the turnips,
the produce of barley was 8-1/4 bushels more than when none had been used.
In the rotation experiments barley was grown after turnips (carted off),
and was followed by beans and wheat. In one series all the crops were
unmanured; in another the turnips received superphosphate; in a third the
turnips received an abundant cinerial and nitrogenous manure.
The mean produce of the six crops of barley obtained in twenty-four years
of rotation was as follows:
------------------------------------------------
|Dressed | Straw and
Character of Rotation. | Corn. | Chaff.
--------------------------+---------+-----------
| bushels.| cwt.
Unmanured continuously | 38-3/8 | 21-3/4
Superphosphate for turnips| |
only | 29-3/8 | 16-1/2
Mixed manure for turnips | |
only | 44-3/8 | 25-1/4
--------------------------+---------+-----------
Mean produce of unmanured |} |
barley in barley |} 21-1/2 | 12-1/8
field during the same |} |
season |} |
------------------------------------------------
The unmanured turnips were so very small in quantity, that the barley in
the first series was practically grown after a fallow; this barley,
however, was a much larger crop than that grown after turnips manured with
superphosphate only, the available nitrogen of the soil in this case being
exhausted by the turnips.
In the last series the residue of the abundant manure applied to the
turnip crop suffices to produce a good crop of barley.
_Qual., Uses, &c._ Its employment and value as food, and in the
manufacture of malt, are well known. It forms good wholesome bread well
adapted for persons who live luxuriously; but which, for the abstemious
and the delicate, is inferior to that made of wheat, as it is rather less
nutritious, and less easy of digestion, and commonly proves laxative to
those unaccustomed to its use. Barley-flour and barley-meal are also more
perishable than wheat-flour; being very apt to acquire a hot nauseous
taste, which even the heat of the oven does not remove. In a medical point
of view, barley is regarded as the mildest and least irritating of the
cereals. It has always been in high estimation as a demulcent and
emollient. The decoction (BAR'LEY-WATER), made with pearl barley, is a
common and useful drink in inflammatory diseases, particularly in those of
the chest and urinary organs. Among the Ancients, decoctions of barley
([Greek: krathê]) were the principal aliments and medicines employed in
acute diseases.
Barley was extensively cultivated by the Romans and many other nations of
antiquity, as well as by the ancient inhabitants of Gaul. The Greeks are
said to have trained their athletes on it.
The best tests of the genuineness of barley are its colour, freedom from
dust, grit, and insects. The microscope will lead to the detection of any
cheaper grains if mixed with it. It is rarely adulterated, although it is
said to be extensively used for the purpose of sophisticating wheat,
annatto, and roll liquorice.
[Illustration: Barley Starch.]
=Barley, Cau'stic.= Sabadilla.
=Barley, Pat'ent.= _Syn._ FARI'NA HOR'DEI, L. Pearl barley reduced to fine
powder by grinding in a mill.
=Barley, Pearl.= _Syn._ PEARL'ED BARLEY*; HOR'DEUM DECORTICATUM (B. P.),
L.; ORGE PERLÉ, Fr.; PERLENGRAUPEN, Ger. The seeds of _hordeum distichon_
deprived of the husks. That of commerce is usually made by steaming
spring-barley, to soften the skin, then drying it, and grinding it in a
mill with the stones set wide apart, so as to round and polish the grains,
and to separate the whole of the husk except that left in the furrow of
the seed. SCOTCH PEARL-BARLEY and FRENCH BARLEY resemble the last, but are
smaller, being generally made from winter-barley or bigg. FARO DE ORZO is
another variety made from sprat-barley. See BARLEY (_above_).
=Barley, Scotch.= _Syn._ HULLED BARLEY[double-dagger],
POT-B.[double-dagger]; HOR'DEUM MUNDA'TUM, L.; ORGE MONDÉ, Fr.;
GERSTENGRAUPEN, GRAUPEN, Ger. The grains deprived of the husk by a mill,
as noticed above, but less completely, and without rounding them.
=BAR'LEY SUGAR.= See CONFECTIONERY, and SUGAR.
=BARM.= See YEAST.
=BAROM'ETER= (_baros_, weight; _metron_, measure). _Syn._
WEATHER-GLASS[double-dagger]; BAROM'ETRUM, L.; BAROMÈTRE, Fr.; BAROMETER,
WETTERGLAS, Ger. An instrument for measuring the weight or pressure of the
atmosphere. It was invented by Torricelli, of Florence, A.D. 1643.
The barometer is made of several forms, but the principle of its
construction, with the exception of the aneroid barometer, is the same in
each, and essentially consists of a column of fluid (usually mercury)
supported in vacuo, in a glass tube, by the pressure of the atmosphere on
its surface. The annexed figures exhibit the principal varieties at
present known; several of which have been proposed with the view of
improving the original instrument, either by increasing its range, or its
portability. None, however, equal in simplicity, cheapness, and
usefulness, the old forms proposed by Torricelli, and represented by the
figs. 1 & 2. To avoid confusion, the graduated scales and cases of the
instruments are not shown.
[Illustration:
1. Torricelli's cistern barometer.
2. " syphon "
3. Huygen's barometer.
4. " " modified.
5. Wheel barometer.
6. Bernoulli's syphon barometer.
7. Aminton's conical "
8. Gay Lussac's "
9. " " " modified by M. Bunten.
_a_, Tube containing a column of mercury.
_b_, Mercurial cistern.
_c_, A column of mercury supporting another of water, _d_.
_e_, _e_, Weights, one of which floats on the surface of the mercury,
and by means of the cord _f_ moves the index _g_.
_h_, Graduated dial.
_k_, Capillary hole drilled laterally to admit air.]
The construction of a barometer requires the utmost skill and care of a
practised artist, and will therefore be seldom undertaken by the amateur
or experimentalist--a fact which renders it unnecessary for us to enter
into the details here. In the choice of his instrument the purchaser must
greatly depend on the known experience and integrity of the manufacturer;
as nothing but lengthened use, and frequent comparisons with other
instruments, can possibly prove its excellence. An ordinary barometer,
however carefully made, is found to suffer gradual deterioration, from the
external air insinuating itself between the mercury and the glass tube, by
which the perfection of the vacuum is destroyed. Various plans have been
proposed to remedy this inconvenience and source of error. Prof. Daniell
forms the bottom part of the tube, to the extent of about 1/3rd of an
inch, of solid platinum, welded to the glass. This plan has proved
completely satisfactory. Dr Ure proposes the use of platinum-foil for the
same purpose. Before purchasing an instrument it is as well to ascertain
that this has been done. In those called 'STANDARD BAROMETERS' the scale
is movable and adjustable by a delicate screw, so as to enable the
observer to bring the lower point or zero (0) of the scale coincident with
the surface of the mercury in the cistern. Exact contact is readily
effected by making the point, and its image as seen by reflection from the
surface of the mercury, to coincide. In this case the cistern is made of
glass. Provided the ivory scale be connected with the zero-point with a
strip of brass, correction as to temperature is very nearly effected by
this simple adjustment. The WHEEL-BAROMETER is chiefly serviceable as a
domestic or land weather-glass.
Of the many forms of mercurial barometer, that perhaps known as Fortin's
is the best. In this instrument the cistern and the lower portion of the
tubes is shown in the annexed figure.
[Illustration]
[Illustration]
"The cistern is made of boxwood, with a movable leather bottom _b b_, and
a glass cylinder, _b_, is inserted into it above, all except the glass
being encased in brass. In the bottom of the brass box a screw, C, works
on the upper end of which the leather rests, so that by elevating or
depressing this screw, the bottom of the cistern, and with it the cistern
level of the mercury, can also be raised or depressed at pleasure. A small
ivory pin, _p_, ending in a point is fixed to the upper frame of the
cistern, and when an observation is made, the surface of the mercury is
made to coincide with the point of the pin as the standard level from
which the barometric column is to be measured. The tube of the barometer,
the upper part of which is shown in the lower figure, is enclosed in one
of brass, which has two directly opposite slits in it for showing the
height of the column, and on the sides of these the graduation is marked.
A brass collar, _d, d_, slides upon the tube with a vernier, _v, v_,
marked on it for reading the height with the greatest exactness and in
which two oblong holes are cut, a little wider than the slits in the brass
tube. When a reading is taken the collar is so placed that the last streak
of light is cut off by the two upper edges of the holes or until they form
a tangent to the convex mercurial curve. By this means the observer is
sure that his eye is on a level with the top of the column and that the
reading is taken exactly for this point. Fortin's barometer is generally
arranged so as to be portable, in which case the screw, _c_, is sent in
until the mercury fills the whole cistern, by which the air is kept from
entering the tube during transport, the leather yielding sufficiently at
the same time to allow for expansion for increase of temperature. It packs
in a case which serves as a tripod when the instrument is mounted for use.
On this tripod it is suspended about the middle, swinging upon two axles
at right angles to each other, so that the cistern may act the part of a
plummet, in keeping the tube vertical--the position essential to all
measurements."[107]
[Footnote 107: Chambers's 'Encyclopædia.']
_How to Manage a Barometer._--It is of the first importance to have the
instrument hung perfectly perpendicular. This is best effected by means of
a plummet line. It should be placed in a good light, but protected from
direct sunlight and also from rain. If air should accidentally find its
way into a common cistern barometer, it may be got rid of by first fixing
the ivory piston, so as to prevent the escape of the mercury, then by
means of the screw raising the mercurial column nearly to the top of the
tube, then by slowly inverting the instrument and tapping the cistern
gently, the air may then perhaps ascend to the cistern and thus escape. In
transporting a barometer from place to place it is best to carry it by
hand; and if packed it is almost needless to say that the float must be
firmly fixed and the mercurial column raised by means of the screw, so as
to prevent any escape of the metal.
_Reading the Barometer._--The mercury in the cistern must first be brought
by means of the screw to the 'zero,' and then the vernier must be screwed
up so that its horizontal edge forms a tangent to the mercurial curve. The
vernier is an instrument for reading off the graduated scale of the
barometer correctly to 1/100th or 1/500th of an inch.
Buchan gives the following description of the vernier and of the method of
using it: "It consists (see figures _a_ and _b_) of a piece similar to the
scale of the barometer along which it slides. It will be observed from
figure _a_ that ten divisions of the vernier are exactly equal to eleven
divisions of the scale, that is, to eleven tenths of an inch. Hence each
division of the vernier is equal to a tenth of an inch, together with a
tenth of a tenth, or a hundredth, or to ten hundredths, and one hundredth,
that is, to eleven hundredths of an inch. Similarly two divisions of the
vernier are equal to twenty-two hundredths of an inch, which expressed as
a decimal fraction is 0·22 inch, three divisions of the vernier is 0·33
inch, &c. Suppose the vernier set as previously described--that is, having
the zero line of the vernier a tangent to the convex curve of the mercury
in the column. If the vernier and scale occupy the relative positions as
in figure _a_, then the height of the barometer is 30·00 inches, but if
they stand as in figure _b_, we set about reading it in this way: (1) The
zero of the vernier being between 29 and 30, the reading is more than 29
inches, but less than 30 inches, and we obtain the first figure 29 inches.
(2) Counting the tenths of an inch from 29 upwards we find that the
vernier indicates more than seven tenths and less than eight tenths,
giving the second figure seven tenths or 0·7 inch. (3) Casting the eye
down the scale to see the point at which a division of the scale and a
division of the vernier lie in one and the same straight line, we observe
this to take place at line 9 of the vernier; this gives this last figure
nine hundredths or 0·09 inch, and placing all these figures in one line we
find that the height of the barometer is 29·79 inches. This sort of
vernier gives readings true to the hundredth of an inch. If the inch be
divided into half tenths or twentieths, and twenty-five divisions of the
vernier equal twenty-four divisions of the scale, it follows that the
difference of these divisions is two thousandths of an inch."
[Illustration]
A still more divided vernier is always used with the best barometers, and
though a little troublesome to read at first, yet if the method of reading
the simpler one just described be understood, the difficulty will be
easily overcome.
_Uses, &c._ The barometer is employed for ascertaining the amount of
atmospherical refraction in astronomical calculations, for measuring
altitudes, and in prognosticating the weather. For the last purpose, on
land, it sometimes proves a false prophet; but at sea, its monitions are
highly trustworthy. As a mere weather-glass, the indications, as read off
from the scale of the instrument, are generally sufficiently accurate; but
in all observations connected with meteorology, altitudes, astronomy, &c.,
certain corrections must be made; the height of the mercury being
influenced both by the size of the tube and by the temperature of the air
by which it is surrounded, as well as by variations in the weight or
pressure of the atmosphere. (See _below_.)
_Barometrical Corrections_:--
1. As to CAPILLARITY:--This applies to all cistern-barometers formed of
tubes of very small diameters, owing to the mercury assuming a convex
surface in the tube. As the tube increases in diameter, so the depression
of the mercury lessens. Hence, the "interior diameter" of a barometer
"should, in every case, exceed one-fourth of an inch." (Brande.) Syphon
barometers that have each of their legs of equal size, require no
correction, as the depression is equal at both ends.
TABLE _of Barometrical Corrections for_ CAPILLARITY,
_from the_ 'Encycl. Brit.'
--------------------+------------------
Diam. of Tube. | Depression.
--------------------+------------------
·10 inch. | ·1403 inch. +
·15 " | ·0863 "
·20 " | ·0581 "
·25 " | ·0407 "
·30 " | ·0292 "
·35 " | ·0211 "
·40 " | ·0153 "
·45 " | ·0112 "
·50 " | ·0083 "
·60 " | ·0044 "
·70 " | ·0023 "
·80 " | ·0012 "
--------------------+------------------
2. As to TEMPERATURE:--These depend on the expansion of the mercury, and
of the scale on which the divisions are marked. The rule for reducing an
observed height to the corresponding height at the freezing-point, or 32°
Fahr., the usual standard temperature, is--Subtract 1·10000th part of the
observed height of the barometer for every degree of Fahr. above 32° at
the time of the observation. Or--
(obs. t. - 32) × obs. h. × ·0001 = corr. req.
_Measurement of Heights by the Barometer._--When a barometer is at the
foot of a mountain, the pressure it sustains is greater than that to which
it is subjected at the top, by the weight of the column of air intervening
between the top and the bottom.
The height can be obtained from the following table by calculating the
number of feet which must have been ascended to cause the observed fall;
and then making a correction for temperature by multiplying the number
obtained from the table, which may be called A, by the following formula:
_t_ is the temperature of the lower and _t'_ of the upper station:--