PRIMARY ANIMAL FLUIDS, 247 



The moft diftinguifliing charadleriftic of sibumen h the pro-Dlftinguiflilng-- 

 perty of being coagulated by heat, which forms an ^^^^''^^''bumefoa^u-*^'' 

 and eafy teft of its prefence, when it exifts in a compound lated by heat. 

 animal fluid in any conliderable proportion. In order to af- 

 certain bow fmalF a quantity of albumen could by this means 

 be rendered vifible, I added 13 grains of the white of the 

 egg to 87 grains of water, and thus formed a fohition, one 

 grain of which contained -— grain of pure albumen. FiveOnc thoufandth 

 grains of this fohition were then added to 95 grains of w'ater,P^^.'|[^JJ^[^J^. 

 lb that 100 grains of water contained y^ grain only, or -j-^t^^ 

 of its weight of pure albumen. This was expofed to the heat 

 of boiling water, and a perceptible opacity was produced in 

 the fluid. 



The effects of the oxymuriate of mercury were next tried.— oxymunate of 

 One drop of a faturated folution of this fait, added to 100 "^^'^^^7 P'^"' 



r • n ' • n piUtCS it} 



grams ot water, contaming t-o'^c of its weight or albumen, 

 produced a very evident milkineis; after fome hours a curdy 

 precipitate feparated and fell to the bottom. A folution of 

 half the ftrenglh, containing only ^^^-^ ^^ '^^ weight of albu- 

 men, was then tried by the fame re-agent, and even in this 

 inftance, a fufficiently obvious eflfedl was produced. 



The nitro-muriate of tin is a powerful coagulater of albu-— as doesnitro. 

 men in its unmixed ftate, but I found it not to be fo delicate "^"'"'''^^ ^ ^"» 

 a teft as the oxymuriate of mercury. One hundred grains 

 of water, containing ^ grain of albumen, i. c. y-^o ^^ *^* 

 weight, was not afi'efled by this re-agent until after fome hours, 

 when the fluid exhibited a degree of milkinefs. 



In order to afcertain the efledts of tannin upon albumen, I— and tannla, 

 macerated half an ounce of powdered galls in half a pint of 

 water for fome hours, and filtered the fluid, A deep brown 

 tranfparent liquor was produced, 100 grains of which I found 

 by evaporation to contain 2| grains of folid refiduum. Equal 

 parts of this preparation of galls and of a folution ofalbumen> 

 in the proportion of one part to 1000 parts of water, were 

 mixe^ together; at firft no efFed could be perceived, but after 

 fome time an evid.ent precipitate was formed and flowly fub-» 

 Tided. 



The aqua lithargyri acetati, or extra6l of Goulard, is anGoulard throw* 

 a£live precipitant of feveral animal fluids; when dropped Into^^^^^'^j 

 a flrong folution of albumen, a vqtv copious and dejife pre- . 

 9ipitate is immediately formed. 



It 



