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co'o^ir, t^e ingrcdien's nf which are well combined with each oth-r, and which is very fohib!e in water. It has an animal fmell, which, however, the cloths get rid of, by bein^ walhed, and expofed to the air.

44 The various experiments I have made on this fubje£r. have been attended with the following refnl ts:

*'■ i. As foon as the wool is thrown into the bailing ley, its fibres adhere to each other, and a very flight degree of agitation is fufficient to render itsfolution complete.

"*. In proportion as frefii woo! is added, the ley gradually acquires colour and confidence.

*' 3. The foap has more or lets colour in proportion to the cleannefs and whitetiefs of the wool made life of.

** 4. Hair of a coarfer kind, which happens to be mixed with the old wool, is diSolved with more difficulty.

44 5. The quantity of wool which ley is capable of dilTolving depends Ajjx>n its ftrength, its caufticity, and its degree of heat. Two pounds, three ounces, and three quarters, of caufiic alkaline ley, at twelve degrees of concentration, and at the boiling-heat, diflblved ten ounces and a half of wool. The foap, when cold, weighed one pound and four ounces.

44 A fimilar quantity of alkaline ley, of the fame degree of cauflicity and heat, in which I diflblved four ounces of wool, did not thereby acquire fufficient confluence to be capable of being ufed for the various purpofes for which this foap is intended.

44 Another fimilar quantity of •ley, of four degrees of concentration, could not diflblve more than

two ounces and feven drams of wool. The foap was of a good confidence, and, when cold, weighed fourteen ounces.

44 6. In proportion as the wool is diflblved in the ley, the fotvent power of the alkali grows weak, and at laft it will diffol vc no more. When we obferve that the wool, upon being ffirred in the liquor, is no longer diflblved, it is then time to ftop the procefs.

44 I (hall now pant out what means are to be employed, in every woollen manufactory, to preparethe foap which will be wanted in it.

44 On the Cbcict and Preparation tf tit Materials.

44 The materials requifite to form this foap are only two; alkaline fubftances, and wool.

u The alkaline fnbftances may be procured from t1* allies of any fires where wood is burnt; and the ley is to be made according to the, common well-known procefs. — Quick-lime is to be Hiked with a final 1 quantity of water, and the pafte formed thereby is to be mixed with the allies, (they being firft palled through a fieve,) in the proportion of one-tenth part of quicklime, by weight, to the quantity of allies made ule of. The mixture mould be put into a ftone vriTel; (as wooden veflels not only colour the ley, but are themfelves mix:!} injured by it;) and water is then to be poured upon it, in fuch q 1 inttty as to cover it, and rife fome inches above it. Thefe are to be left together for a certain time, and then the ley is to be drawn off, by an aperture made for that purpole, at the bottom of the vellel. It is beft not to draw off the ley, till the moment when it is to be ufed: itsftrength (hould be from four to fif1$ teen teen degrees; but the degree of concentration is a matter of very little confequence, fince all the difference that refults from making ufe of a weak ley or ftrong one, is, that a greater or a lefs quantity of wool will be diffolved.

"The pot-afh of commerce may alfo be made ufe of; it is to be employed in the fame manner as the wood allies, but with one third of its weight of quick-lime.

"With reipeft to the choice of the wool, every.one knows, that in the making of woollen cloths, blankets, and all other kinds of woollen good?, a feries of operations is performed, from the firft wafliing of the wool to the finifhing of the cloth, &c. in each of which there occurs a lofs, more or lefs confiderabfe, of a portion of the original material. The water in which the wool i« waflie fc the floor on which it is fpread, and. the warehoufe in which it is depofited, exhibit fuiricient proofs of this; fo alfo do the operations of beating, carding, fpinning, and weaving the wool, and thofe of fhearjng, combing, and fulling the cloth. It is indeed true that the fcattered wool, produced from thefe various proceffes, is collected with fome care; but many of them are of fuch a nature, that the wafte wool refulting from them, either is dirty, and mixed with other fubftauccs, or it is cut fo fhort, that it is rendered incapable of being again ufed: in either cafe, the manufacturer throws it on the dunghill. The making of the foap here defcribed furnifhes him with the means of bringing all thefe inro ufe; nothing more being requifite than to col left them in the bafkets in which the wool is wafhed, and to wafh them carefully; as well for the fake of cleaning them, as to feparate from them all foreign iub

ftances. When wafhed they may be laid by till wanted. ,

"We may alfo, with equal advantage, make ufe of the cuttings and fhreds of woollen cloth, which are found in the fhops of woolendrapers, tailors, 8cc. and likewifeof all forts of garments, or other woollen articles, after they have been worn till they will ferve no longer.

"On tie Preparation of the Soap.

"When the ley is made and the wool procured, nothing remains to be do:ie, but to bring the ley to a boiling-heat in a common caldron. When it is brought to that degree of heat, the wool is to be thrown in, a little at a time, and the mixture is to be ftirred, that the folotion may go on the fafter. A frefc quantity of wool (hould not be added, until the preceding quantity i« diffolved; and the procefs ftould be flopped, as foon as we find that the liquor will not diffolve anymore wool.

"It has been afcertained, by trials in the large way, made by Michel Fabriguette, with foap of* this kind, which he prepared according to my inftru&ions, that fucn loap fconrs the cloths, felt» them, and. foftens them, perfectly well; but there are fome obfervations to be made, refpeclingits ufe, which are too important to be omitted.

"Firft, when this foap is not prepared with fufticient care, or when it is made with dirty or coloured wool, it is apt to give the cloths, Sec. a greyifli tinge, which it is very difficult to remove. If the cloth is intended to be dyed, this tinge is of no confequence; but it would injure that fine wliaecolour, which, in certain cafes, is intended to be given, or to be preferved. This tinge, however, may he prevented, by a very careful felection of the materials for making the foap which is meant to be employed for fuch delicate pnrpofes.

"Cloths, &c. fulled with this foap, acquire, as was faid before, an animal fmell, which, without be^ ing very ftrong, is neverthelefs unpleafant; but water and air never foil to remove it. • .

"Having fucceeded in fulling ivoollen cloths by the ufe of this foap,I attempted to ufe foda, in the place of pot-afli, and thus to form (according tothe procefsabove defcribed) a hard foap, fit for the operations of dying cottons; and my experiments fucceeded beydnd my expectations.

"Forty-fix pounds of foda-ley (of eighrdegrees) diffolved,in a boiling-heat, five pounds of wool ; and afforded, when cold, fixteen pounds fourteen ounces of foap, fufficiently hard to keep its form.

"The firft quantities of wool thrown into the foda-ley are eafily diffolved; but it may be obferved, that the liqror gradually grows thicker, and that the diflolution becomes more difficult and flower. "The ley, by the wool firft diffolved in it, acquires a green colour; it afterwards grows black; and the foap, when cold, ftill retains a blackifli green colour.

"This foap has been made ufe of, in every different mapner, and under every form in my manufactory for dying cottons; and I am now fatisfied that it may be employed, inflead of the faponaceous liquor we are accuftomed to make from ley of foda and oil, for the purpofe or preparing the cottons. 1 have conftantly obferved, that if fuch a quantity of this foap be diflblved in cold water as will render the water milky, and the cotton be worked

therein, in the nfual well-known manner, jt will, by being paffed three times through the liqnor, and dried each time, be as firongly difpofed to receive the dye, as cotton which has been feven times paffed through the faponaceons liquors commonly nfed. This will not be thought very affonifhing, when it is confideredth3t animal fubftances are very fit for difpofing thread and cotton to receive the colours with which they are to be dyed; and that the intention of feveral of the operations performed upon them, previous to their being dyed, is merely to impregnate them with fuch fubftances.

"It is neceffary to remark, that cotton, by being paffed through a folutionof this foap, acquires a grey tinge, very much like that which is given to it by aluming; although the common faponaceous liquors give it a beautiful white colour. This grey colour, however, is no difadvantage to cotton which is intended to be dyed, as we have already remarked with refptft to woollen cloths.

"In confirmation of what I have faid above, refpeftingthe advantage to be derived from nuking ufe of this foap, I may add, that after having impregnated fome cotton with it, according to the ufual method, I made it pals through all the proceffes which wool undergoes, in order to be dyed of a fcarlet colour. The confequence was, that the cotton was thereby dyed of a deep and very agreeable flefh-colour; whereas cotton which had not been prepared in that manner, came out of the bath almoft of its natural colour. This firft trial promifes advantages which 1 mean to purfue. ■ "It may be right to obferve, that this foap of wool may advantageon fly be made ufe of, inftead of /4 comcommon foap, for domeftic pyrpofes. I have employed it with the greateft iuccei's, in wafhing linen; and it is particulaily efficacious in ftouiing woollen garments, &c. I have no doubt that the facility and economy with which its preparation is attended, will caufe its - ufe to be extended to many other purpofes; in :he mean time, I thought ,it right to give an account

of the various ways in which I have applied it.

"1 (hall only add, that a* the foap here delcribed gives the woollens and cottons a grey tinge, which is very difficult to remove, it follows that it cannot be ufed for walhing linen, unlefs it be made of white wool, carefully felected, and well wafhed."

Interesting Account of the Effects produced on the Humah Body, by the Internal Use of Nitrous Acid, and 01 the BtNEFit derived from it in the Cure of Diseases, by Mr. Scott of

Bombay.

[Fiom Drs. Duncans' Annals of Medicine for the Year 1796.]

'' rT,KE following interefting arJL title of medical news has not proHahlv fallen into the hands of many oi our readers; and to all of then, it wi I, we doubt not, appear fo fingular as to defervc particular attention. If the obiervations maJe by Mr. Scott (hall be confirmed by the experience of others, the nitric acid will afford a moft valuable remedy for combating dileafes, againft which the remedies commonly employed are often attended with fo much inconvenience.

Letter To Sir Joseph Banks.

Bombay, ittb May, 1796. "1 embrace an opportunity of fending you a fhort account, that I have juft published, of the effects of the nitrous acid on the human body. As 1 have long made ufe of thU artive agent, and in a great variety of cafes, I am peifnaded that I have not been deceiving myfelf. Another paper will fhortly bepublifhed on this fubjecl, which I fhall alio take the liberty of fending you.

The acid that I now employ for internal ufe, is procured from a mixture of three parts or" alum, and one of nitre. 1 have no objection » my name being ufed on this fubjict.; for 1 really believe that fuch a remedy would be highly ufefdl to mankind, if judicioutly employed, efpecially in warm climates, where a tendency to animaiization gives a particular character to all our dileafes.

I am, Stc.

VV. Scott.

Account oftlx EffeSlsof the Nitrous Acid on the Human Body, txtraR* riifrom the Bombay Courier^ April 30, 1796.

The following attempt to extend a little the limits of the healing art, is inferibed as a tribute of refpecr. to the character of Dr. James Anderfon, phyfician-genera! at Madras.

"In Auguft 1793, I employed myfelf for Tome time in making experiments on the bile, a fecretion that is connected in a great degree with many of the difeafes of this oountiy. I wifhed to unite fome of the calces of mercury with the refinous matter of that fluid; for I imagined that I might diScover fome chemical affinity be:ween thofe l'ubftances, and be able to fee by what means this metal is fo lingulatly qualified for removing obstructions of the liver.

"I had collected, for experiment, a quantity of the refinous bafeof the bile of a buffalo, which I had Separated very carefully from its foda, and from the lymphatic matter with which it is united. I had put a dram or more of this fubftaocc into a veflel, to which I added about half of the fame weight of the red calx of mercury, with ten or twelve ounces of water. On heating the whole together, I was furpriled to obferve, that the bafe of the bile became remarkably more Soluble in the water. I cannot fay that 1 observed the red colour of the calx in any great degree altered; but it is known to retain its brilliancy with different quantities of oxygene. I filtrated this bitter Solution, which depofited the bafe of the bile, as the water evaporated in the ordinary heat of the atmofphere. I (hall at another time confider this Subject with a little more attention.

"M. Fourcroy has obferved, that waterdiSSolves a Small portion of the baSe of the bile. In this experiment a considerably larger quantity was taken up than water could have diSfolved, which I attribute to the oxygenation of the reGn by the pure air of the calx. 1 had fome realbn to think, that obstructions of the liver do often confitl of a deposition of the refin of the bile, which, I now began to SuppoSe, might be rendered Soluble in the animal fluids, by the pure air of the mercurial preparations that are givtn for the difeafe. I have Seen

livers, on the diffe£tion of the dead, of a pearl colour, and much enlarged, which 1 fulpeft were compofed in a good meaSure of rhis retinous matter. I have even found it, from accurate trials, in a considerable quantity, in the Subftance of a liver that was apparently without diSeife. Is the well-known effect of new grafs, in diffolving the biliary ralcah of the grill-bladder, that cattle get in the winter-time, to be accounted for from the pure air of grien and acefcent vegetables r

"It is acknowledged, that all the calces of mercury which are uSed in medicine, contain a quantity of pure air; but I know of no direct experiment having been hitherto made, to prove that the effect of mercury in difeafes of the liver, or in other maladies, depends on this principle, arid not on the metal iti'elf. The experiments, that I had made on the bafe of the bile, inclined me to wifh to take myfelf a quantity of pure air, united to fome Subftance for which it has no great attraction. I reflected on the different ways that are employed by chemifts tr> oxygenate inanimate matter; for I believed that the lame chemical attractions would produce a Similar effect in the living body, although they might be difturbed in their operation by the vitality of the machine, and the variety of the principles of which it is compnfed.

"The nitric acid, as may be fuppofed, was one of the firlt Subftances that occurred to me as fit for my purpofe; for it is known to contain about four parts of vital air, unired to one of azote, with a certain proportion of water. Thefe principles can be Separated from each other by the intervention of many other bodies, as chemifts find every day in their operations. I was led, befides, to give a preference to the nitric acid, from obferving, that it dif

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