10S Scientific Intelligence. 



twice its weight of water cooled down to 104° lo 120°. After standing 

 a day to allow the fat to separate, it was mixed with three parts of 

 manganese and thirty of water, and submitted to distillation. 



With chromic acid, the best proportions are three of sulphuric acid, 

 two of bichromate of potash, and thirty of water; the caseine is dis- 

 solved as before in the acid, and afterwards mixed with the salt dis- 

 solved in ten parts of water; the action immediately commences with 

 violence, but is moderated by adding the remainder of the water, and 

 the distillation goes on calmly. 



The separation of these bodies was effected by saturating the acids 

 with carbonate of soda and distilling over the neutral products, which 

 were afterwards separated by careful fractional distillation. The salts 

 were decomposed, and the acids first separated by fractional distillation, 

 and afterwards by crystallization of their salts. 



The existence of all the acids above named, was proved by careful 

 analysis. 



The butyric aldehyde C 8 H 8 2 , is sparingly soluble in water; it 

 boils at 154°-158° F., and has a"* specific gravity of -800 at 59°. It 

 tastes like acetic aldehyde, but soon becomes acid on exposure to the 

 air from the formation of butyric acid; it reduces oxyd of silver when 

 boiled with it, and forms a butyrate ; with a solution of nitrate of silver 

 and ammonia, it gives a metallic mirror. It reacts like acetic aldehyde 

 with potash and ammonia, giving with the latter a crystalline compound 

 closely resembling in its properties aldehyde-ammonia. With sulphu- 

 retted hydrogen, it yields a base resembling thialdine. 



The characters given by the author differ somewhat from those as- 

 cribed by Chancel to the butyral obtained by the distillation of butyrate 

 of lime, which he regarded as the aldehyde o( butyric acid. 



[It is to be observed that the aldehyde of Dr. Guckelberger approaches 

 nearly in its boiling point to that found by calculation, 145 c '2 F., while 

 Mr. Chancel found the boiling point of his liquid to be 203° F.] 



The supposed metacetonic aldehyde could not be obtained pure; a 

 liquid of an ethereal odor, boiling between 130° and 149° F., gave num- 

 bers closely agreeing with the formula C 6 H 6 2 . Its specific gravity 

 was 0*79, at 59° F. ; it became acid by the action of the air, but did not 

 reduce a solution of silver. From the small quantity of it, the author 

 was unable to make a more minute examination. 



The products by chromic acid differ from those obtained by the ac- 

 tion of sulphuric acid and manganese, in containing valeronitrile and 

 prussic acid, which are azotized substances. Their absence in the 

 former is explained by the fact that these are at once decomposed by 

 an excess of sulphuric acid, inlo valerianic and formic acids and am- 

 monia. The residue from the process with manganese evolves a great 

 amount of ammonia with lime, while that from chromic acid yields 

 scarcely a trace. 



The fibrine and albumen employed were obtained from blood ; these 

 substances and gelatine were treated in the same manner as caseine. 

 With manganese and sulphuric acid they all gave the same aldehydes 

 and acids as caseine, without a trace of prussic acid ; the relative pro- 

 portions of these however varied; with chromic acid, the distillates 

 were all rich In prussic aeid, and afforded valeronitrile, besides all the 



