American Journal of Pharmacy and the Sciences Supporting Public Health, Tom 19

Przednia okładka
Philadelphia College of Pharmacy and Science., 1847
 

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Strona 47 - Having thus described the nature of my invention, and the manner of performing the same, I would have it understood that I do not confine myself to the details...
Strona 100 - It cannot be purified with nitric acid, nor with aqua regia, for part of the platinum metals will thereby be dissolved, or, at best, so suspended in the fluid that filtration is impossible.
Strona 192 - Pure copaiba is said to dissolve a fourth of its weight of carbonate of magnesia, with the aid of a gentle heat, and to continue translucent, the presence of a small proportion of any fixed oil being indicated by the product being opaque. This, again, is one of the tests given in the Edinburgh Pharmacopoeia. This test was tried on specimens 1, 2, and 3, and the results were nearly the same in each case.
Strona 140 - A magnificent tree of fifty, or more probably 100 years' growth, is cut down, the bark stripped off, and the milky juice collected and poured into a trough formed by the hollow stem of the plantain leaf; it quickly coagulates on exposure to the air; but from one tree, I was told that not more than 20 Ibs. or 30 Ibs. are procured. I believe, however, that the juice may be obtained by tapping the tree, and that it might thus be made to produce in moderate quantities for many years; but this mode is...
Strona 68 - ... maintained for 12 hours, and assisted by a current of dry hydrogen, suffices to expel these three bodies, so that the nicotine passes pure and colourless, when the temperature is subsequently raised to 356°. 2 Ibs. of good tobacco, grown in the department of Lot, is capable of yielding by this process from 50 to 60 grms. of nicotine. The formula for nicotine, C*° HM Na, proposed by M.
Strona 281 - When an alkaline carbonate is used, powdered charcoal, to the amount of more than 30 per cent. of its weight, may be added, without destroying the fluidity of the mixture if the temperature is raised to a full red. When the potash or soda is in a caustic state, a larger proportion of charcoal may be added; or, what is more advantageous, the mixture will remain fluid, although the heat be raised not so high.
Strona 138 - ... observed in the hands of a Malayan woodsman the handle of a parang, made of a substance which, appeared quite new to me. My curiosity was excited, and on inquiry I found it was made of the gutta percha, and that it could be moulded into any form by simply dipping it in boiling water until it became heated throughout, when it became plastic as clay, and when cold, regained, unchanged, its original hardness and rigidity. I immediately possessed myself of the article, and desired the man to fetch...
Strona 143 - ... dissolves entirely in alcohol. The solution yields, on cooling or evaporation, colourless crystals of pure sulphocyanide of ammonium. Only a small quantity of sulphuret of ammonium is requisite to convert, in the presence of an excess of sulphur, unlimited quantities of cyanide of ammonium into sulphocyanide ; because the sulphuret of ammonium, when reduced to the state of monosulphuret, constantly reacquires its power of dissolving sulphur and transferring it to the cyanide of ammonium. The...
Strona 290 - ... chromic acid in a retort, a very brisk reaction ensues, and upon applying a gentle heat there passes over a clear liquid, containing a considerable amount of aldehyde, with a faint trace of acetic and probably formic acids. The presence of the aldehyde is readily shown by adding a few drops of the liquid to a solution of nitrate of silver previously curdled by ammonia, and then gently heating the mixture. The oxide is speedily reduced, forming a brilliant metallic coating on the sides of the...
Strona 106 - Rohiquet's process, is made by heating to low redness a mixture of one part of porcelain clay, one and a half of sulphur, and one and a half parts of anhydrous carbonate of soda, in a covered crucible so long as vapours are given off. When opened, the crucible is usually...

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