PUTREFACTION. 



It is, therefore, juftly obfcrvod by lord Bacon (Nat. Hid. 

 cetit. iv.) that an enquiry into the means of preventing or 

 ftaying putrefaflion is of excellent ufe in phyfic. Sir John 

 Pringle lias made many curious experiments with a view of 

 deteririning the power of certain fubftances to promote or 

 to prevent putrefaftion, together with remarks on this fub- 

 jeft, which are publifhcd in the Phil. Tranf. vol. xlvi. p. 480. 

 525. 550, and by way of appendix to his Obfervations on 

 the Difeafes of the Army. From the experiments of tliis 

 learned and judicious phyfician, it appears, that falts of 

 every kind, whether acid, alkahnc, or neutral, fixed or vo- 

 latile, as well as the allringent and gummy-refmous part of 

 vegetables, all of them refill and mod of them correct pu- 

 trefadion ; aud he purfued this branch of enquiry fo far as 

 to enable hira to form a table {hewing the comparative anti- 

 feptic power of the feveral fubftances, that of fea-falt being 

 the ftandard. See this table under the article Antiseptic. 



Of all refinous fubftances, he found that camphor re- 

 fifted putrefaftion moft; powerfully ; its antifeptic power 

 being three hundred times greater than that of fea-falt. 

 Decoftions of wlieat, barley, and other farinaceous grains, 

 checked putrefaftion, by becoming four. He alfo made 

 experiments to difcover the effefts of mixing vegetable with 

 animal matters. 



Two drams of raw' beef, as much bread, and an ounce 

 of water, being beat to the confiltencc of pap, and expofed 

 to 90° of heat, according to Fahrenheit's thermometer, be- 

 gan to ferment in a few hours, and continued in a fermenta- 

 tion two days. When it began to ferment and fwell, the 

 putrefaftion had begun ; and in a few hours afterwards the 

 I'mell was ofFenfive. Next day the putrid fmell ceafed, and 

 an acid tafte and fmell fuccecded. Frefh alimentary vegeta- 

 bles, as fpinach, afparagus, fcurvy-grafs, produced fimilar 

 effefts as bread on flefh, but in a weaker degree. From fe- 

 veral other experiments, he found that animal fubftances ex- 

 cite the fermentation of vegetable fubftances ; and that the 

 latter fubftances correft the putrefcency of the former. 



By adding faliva to a fimilar mixture of flefti, bread, and 

 water, the fermentation was retarded, moderated, but ren- 

 dered of twice the ufual duration, and the acid produced at 

 laft was weaker than when no faliva was wfed. 



By adding an oily fubftance to the common mixture of 

 flelh, bread, and water, a ftronger fermentation was pro- 

 duced, which could not be moderated by the quantity of 

 fahva ufed in the former experiment, till fome fixed alkaline 

 fait was added, which fait was found, v/ithout faliva, to ftop 

 fuddeuly very high fermentations. 



He did not find that fmall quantities of the following 

 falts, fal ammoniac, nitre, vitriolated tartar, fal diureticus, 

 fait of hartfliorn, fait of wormwood, were feptic, as fmall 

 quantities of fea-falt were. 



Sugar was found to refift putrefaftion at firft, as other 

 falts do, and alfo to check the putrefaction after it had be- 

 gun by its own fermentative quality, like bread and other 

 fermentative vegetables. 



Lime-water made fome fmall refiftance to putrefaflion. 



Port-wine, fmall beer, infufions of bitter vegetables, of 

 bark, and the juice of antifcorbutic plants, retarded the 

 fermentation of mixtures of flefti and bread. But an 

 unftrained decoftion of bark confiderably increafed that 

 fermentation. 



Lime-water neither retarded nor haitened the fermenta- 

 tion of fuch a mixture ; but when the fermentation ceafed, 

 the liquor was neither putrid nor acid, but fmelt agreeably. 



Flelh pounded in d- moi-tar was found to ferment fooner 

 than that which had not been bruifed. 



The tough inflammatory crufl of blood was found to be 



moft putrefccnt, rcxt to which the crafl'amentura, or red 

 coagulated maf'^, and laftly the ferum. 



Charcoal is a powerful antifeptic : hence all forts of glafs- 

 veflels and other utenfils may be purified from long retained 

 fmells of every kind, in the eafieft and moft perfect manner, 

 by rinfing them out well with charcoal powder, after the 

 grofliir impurities have been fcowered off with fand and 

 potafh. Rubbing the teeth and waftiing out the mouth 

 with fine charcoal powder will render the teeth beautifully 

 white, and the breath perfeftly fweet, when an offenfive 

 breath has been owing to a fcorbutic difpofition of the gums. 

 (Crell's Journal, vol. ii. ) Meat alfo, which is a little tamted 

 with putridity, may at once he made fweet by charcoal ; and 

 it has been faid, tliat common raw fpirits agitated with char- 

 coal v.'ill be deprived of their bad flavour, but they are apt to 

 refume their old flavour, if kept in the cafl< only a few 

 weeks. 



The experiments of the author of the " Elfai pour fervir 

 a I'Hiftoire de la Putrefaclion," fliew that metallic falts, 

 refinous powders, extrafts of bark and opium, are very 

 powerfully antifeptic, and that falts witli earthy bales are lefs 

 antifeptic than any other falts. 



The fame ingenious phyfician made fome attempts to- 

 wards the fweetening of corrupted flefli by means of mild 

 fubftances. For this purpofe he put a piece of putrid flefti 

 into an infufion of chamomile flowers, which was renewed 

 twice or thrice in as many days, and its fweetnefs and firm 

 texture were recovered. Several pieces of putrid flefti were 

 alfo fweetened by repeated aftufions of a Itrong decocHon 

 of the bark ; and he conftantly obferved, that not only the 

 corrupted fmell was removed, but a firmnsfs reftored to the 

 fibres. The corrupt yolk of an egg, diluted with water, 

 was fweetened by mixing it with a ftrong infufion of chamo- 

 mile flowers. He found alfo that decoftions of wormwood, 

 of the bark, and infufions of chamomile flowers, and of 

 fnake-root, preferved yolks of eggs for a longer time than 

 water, even with th(*'addition of a confiderable quantity of 

 fea-falt ; and that they were preferved better by fait of 

 hartfliorn than by four times tiie weight of fea-falt. Ox-gall 

 was kept for fome time from putrefaftion by fmall quanti- 

 ties of lev of tartar, fpirit of hartfliorn, crude fal ammoniac, 

 and the faline mixture ; and ftill longer by a decoction of 

 wormwood, infufion of chamomile flowers and of fnake- 

 root, and by folutions of myrrh, camphor, and fait of 

 amber. The ferum of human blood was preferved by a 

 decoftion of the bark, and an infufion of fnake-root, as 

 efleftually as flefli. See Antiseptic. 



For an account of fir John Pringle's experiments and ob- 

 fervations with refpetl; to thofe fubjefts that haften or pro- 

 mote putrefaftion, fee Septics. 



Dr. Macbride's experiments confirm many of thofe above 

 related, efpecially thofe which ftiew that the fermentation of 

 vegetable fubftances is increafed by a mixture of animal or 

 putrefccnt matter, that the putrefcency of the latter is cor- 

 rected by the fermentative quality of the former ; and that 

 the putrefaftion and fermentation of mixtures of animal 

 and vegetable fubilances were accelerated by additions of 

 abforbent earths and of Peruvian bark. He alfo found, 

 that although unburnt calcareous earths were feptic, quick- 

 lime and lime-water prevented putrefaftion, but that they 

 deftroyed or diflblved the texture of flefli. 



From his experiments we learn alfo, that acids, even 

 \Then greatly lowered, have a ftrong degree of power to 

 refift putrefaftion, and alfo to correft it ; but that they 

 deftroy the texture of the fubftance whofe foundnefs they 

 were fuppofed to reftore ; that falts in general, by a pro- 

 perty which is common to them all as falts, have the fame 



power. 



