Footnote 262:
The vegetable kingdom presents us with many natural compounds of this
kind; several of which might be pressed into the service of medicine
with much advantage. With respect to the number and variety of such
substances, it must be confessed that our Pharmacopœia contains but a
meagre bill of fare.
Footnote 263:
The same reasoning will explain why English hops, that contain more
Gallic Acid and Tannin than those imported from the Continent, are
found to be superior as preservatives of beer.
Footnote 264:
Therapeutics, vol. 2. p. 470.
Footnote 265:
This subject has been ably illustrated by Mr. R. Phillips, in his
translation of the London Pharmacopœia, by a series of vary striking
and instructive diagrams.
Footnote 266:
See my work on Medical Chemistry: Sect. Precipitation.
Footnote 267:
An ingenious application of this law has been made for the purpose of
purifying Epsom Salts. See _Magnesiæ Sulphas_; and also my work on
Medical Chemistry, _Art: Solution_.
Footnote 268:
Amœnitates Academ; T. 7. p. 307.
Footnote 269:
See also a paper in the MEDICAL TRANSACTIONS, vol. 2. entitled,
“Several extraordinary instances of the cure of Dropsy, by GEORGE
BAKER, M. D. Read September 9, 1771.”
Footnote 270:
The most subtle of all poisons,—_the matter of febrile contagion_,—is
certainly modified in activity by the degree of moisture in the
atmosphere influencing its solubility; the Plague is said to be most
common in Egypt after the inundation of the Nile, a period at which
the atmosphere is necessarily saturated with water; according to the
account of Sir Robert Wilson, the English and Turkish armies that
marched to Cairo escaped contagion, while the troops that remained
stationary on the moist shore of Aboukir, were very severely visited.
On the other hand, the _Harmattan_, a wind experienced on the western
coast of Africa, between the Equator and fifteen degrees _North
Latitude_, blowing from north-east towards the Atlantic, and which, in
consequence of its passage over a very extensive space of arid land,
is necessarily characterized by excessive dryness, puts an end to all
Epidemics, as the Small Pox; and infection at such a time does not
appear to be easily communicable even by art. _Philosophical
Transactions_, vol. 21.
The difficulty of communicating infection to animals during a dry
state of the air, as remarked on the Western Coasts of Africa, during
the blowing of the _Harmattan_, agrees with some observations on
Plague by the French physicians, as this complaint first made its
appearance in the French army during a moist state of the air in
Syria, when it lay under the walls of Jaffa in February, 1800.
It is a well known fact that volatile bodies are sooner converted into
a gaseous state by the presence of water in the atmosphere; this is
strikingly exemplified by the greater rapidity with which _Limestone_
is burnt and reduced to quick-lime in moist weather, and by the
assistance which is rendered in a dry season, by placing a pan of
water in the ash-pit; so again the perfume of flowers is most sensible
when the air is humid, as during the fall of the evening dew, or in
the morning when the dew evaporates, and is dissipated by the rays of
the rising sun; for the same reason the stench of putrid ditches and
common sewers, is conveyed to the organs of smell much more speedily
in summer previous to rain, when the air is charged with moisture.
Footnote 271:
They are previously calcined, but not burnt to lime, to an extent only
that may destroy their tenacity, and render them fit for levigation.
Footnote 272:
A similar custom is common to the Indians of the whole of Asia, and of
America; for the practice of the South American Indians, see
_Humboldt’s Personal Narrative_. In India, Betel, variously
compounded, is employed for the purpose above stated. The mixture more
commonly used in Ceylon consists of quick-lime, Arecanut, and Tobacco,
wrapped in Betel leaf. On ordinary occasions it is only masticated;
but to repress the painful calls of hunger, the juice is swallowed.
Footnote 273:
Vol. viii. p. 33.
Footnote 274:
Dr. MacCulloch, in illustration of this subject, states, that ink,
paste, and seeds, are among the common articles which suffer from such
a cause, and to which this remedy is easily applicable. With respect
to articles of food, such as bread, cold meats, or dried fish, it is
less easy to apply the remedy, on account of the taste; cloves,
however, and other spices whose flavours are grateful, may sometimes
be used for this end. It is notorious that gingerbread, and bread
containing caraway seeds, are far less liable to mouldiness than plain
bread. The effect of cloves in preventing the mouldiness of ink is
generally known; and the same result may be obtained by oil of
lavender in a very minute quantity, or by any other of the perfumed
oils. Russian leather, which is perfumed with the tar of the Birch
tree, is not subject to mouldiness, as must be well known to all who
possess books thus bound; they even prevent it from taking place in
books which are bound in calf, and near which they may happen to lie.
Paste is another perishable article, and although _Alum_ which is used
by the book-binder will certainly preserve it longer than it would
remain useful without it, still it is not very effectual. _Rosin_,
sometimes used by the shoemaker, answers the purpose better, and
appears to act entirely on this principle; it is however far less
effectual than even oil of turpentine; _Lavender_, and the other
strong perfumes, as _Peppermint_, _Anise_, and _Bergamot_, are
perfectly effectual, even in a very small quantity, and paste may be
thus preserved for any length of time.
Footnote 275:
Medical Logic, Edit. 2. p. 192, _note_.
Footnote 276:
It appears from what has been stated under Section I. B. with respect
to DIURETICS, that some medicines not only assist, but actually DIRECT
the operation of the substances with which they may be associated, and
that many remedies act in unison with those they are joined with; thus
_Nitre_ in conjunction with _Squill_ is diuretic; in conjunction with
_Guaiacum_, diaphoretic; for these reasons I hesitated whether I ought
not to have added a fifth _constituent_, and restored the “_Dirigens_”
of ancient authors; enough, however, has been said to enable the
practitioner to appreciate the importance of such a law of medicinal
combination.
Footnote 277:
Dr. Percival in his Essays, ingenuously exemplifies this error by
stating a case which occurred in his own practice. “I ordered,” says
he, “a combination of Camphor and Balsam of Copaiba in the form of
pills, but the apothecary informed me that he was unable to form them
into a mass, since they liquefied like treacle.” I may here observe
that the addition of a small portion of the coagulated yolk of an egg,
would have rendered the mixture practicable.
Footnote 278:
This would occur, if in making the Pilulæ Ferri Compositæ, we were to
substitute the Liquor Potassæ for the Sodæ Sub-carbonas.
Footnote 279:
The “Pharmacopœia Bateana” contains a Formula for a “Tinctura
Antiphthisica,” which is stated to be “a truly good medicament in
those consumptions which proceed from ulcers of the lungs.” The
following is the Receipt—℞. Sacch: Saturn: ℥ij—Sal Martis ℥j—Infus:
Spir: Vin: ℔j—Dose from twenty to forty drops. In this case an
insoluble Sulphate of Lead must be formed, which will render the
medicine, as far at least as its saturnine effects are concerned,
completely inert!
Footnote 280:
This fact has been very satisfactorily proved by the failure of the
practical attempts which were made by Dr. Macbride of Dublin, to
improve the art of tanning leather by the use of Lime-water, instead
of plain water, which he conceived would extract the virtues of Oak
Bark more completely. The reader who is desirous of a more detailed
account of this plan must refer to Phil. Trans. Vol. lxxiii. part 1,
Art. 8.
Footnote 281:
We trust these observations will not create any alarm in the worthy
Citizen; he may, with as much safety as pleasure, continue the
laudable practice of regaling himself and friends with a cup of strong
tea, in spite of the Turtle soup they may have taken, and that too
without the least danger of converting their stomachs into tanneries,
or their food into leather.
Footnote 282:
For a highly ingenious, and important extension of these views, see
Aqua Marina. (Note.)
Footnote 283:
M. Dive, an apothecary of Mont de Marson, has lately announced that a
current of carbonic acid, when passed through a solution of Tartrate
of Potass, partly decomposes it; and he ascribes to the same agent the
production of the Bi-tartrate in the juice of the grape during its
fermentation: accordingly, by mixing neutral tartrate with fermentable
materials, we shall produce Cream of Tartar in the fermented liquor.
Journal de Pharm. Octob. 1821. p. 487.
Footnote 284:
In one remarkable case related by this Physician, the operation of the
unbruised mustard-seed is stated to have been promoted by combining it
with a decoction of _Broom-tops_. Query, Was not the adjunct in this
case the only efficient part of the remedy?
Footnote 285:
The word “_Venenum_,” was employed by the ancients to signify both a
_poison_ and a _medicine_; in the former of these acceptations it is
used by Virgil in the following passage:
“Picus equum domitor, quem capta cupidine conjunx
Aurea percussum virga, versumque VENENIS,
Fecit avem Circe, sparsitque coloribus alas.”
Æneid. Lib. vii.