398 Royal Society : — 



Schlippe* has discovered an acid belonging to the oleic series, 

 which lies between acrylic and angelic acids. 



After the saponification of the fatty acids contained in this oil, 

 which are stearic, palmitic, nijaustic, and lauric acids, besides 

 probably some higher members of the oleic series, an almost 

 black subjacent liquor remains, which contains the new acid 

 along with other substances. For the purpose of separation, 

 this liquid was distilled, on which an acid liquid passed over. 

 This was neutralized with baryta, and the baryta salt distilled 

 with tartaric acid, when oily drops passed over along with the 

 acid liquor, and towards the end of the operation crystals of an- 

 gelic acid were deposited in the condenser. This distillate was 

 neutralized with baiyta, and again distilled with tartaric acid, 

 and this treatment repeated. Finally, some of the baryta com- 

 pound was distilled with aqueous phosphoric acid. In the receiver 

 the acid was obtained in the form of limpid oily drops along with 

 a small quantity of water, in which it is tolerably soluble. It 

 contained, however, other acids ; and for the puz-pose of separa- 

 tion, recourse was had to partial distillation. Of the acid which 

 first distilled, a silver salt was prepared, which gave on analysis 

 numbers agreeing with the formula C^ H^ Ag 0"*, which would 

 be the formula of the silver salt of an acid between angelic and 

 acrylic acids. Schlippe names the acid crotonic acid. 



The acids of this series decompose when heated with excess of 

 caustic potash into acetic acid and an acid of the same series : 

 thus angelic acid decomposes into acetic acid and propionic acid ; 

 oleic acid into acetic acid and palmitic acid. In like manner, 

 crotonic acid, if it belong to this series, ought to decompose into 

 two equivalents of acetic acid, 



C8 H6 04 + 2K0 HO = 2C4 H^ KO" + 2H, 



Crotonic acid. Potash. Acetate of potash, 

 which Schlippe found to be the case. 



Crotonic acidhas neither inliammatorynorpurgative properties. 



XXXIII. Proceedings of Learned Societies. 



ROYAL SOCIETY. 

 [Continued from p. 229.] 

 February 18, 18.58. — Leonard Horner, Esq., V.P., in the Chair. 

 ^j^HE following communication was read : — 

 -■- "On the Functions of the Tympanum." By James Jago, 

 A.B. Cantab., M.B.Oxon, Physician to the Eoyal Cornwall Infirmary. 

 As in my present effort to obtain further light upon some of the 

 still obscure points in the physiology of the ear I have been prima- 

 rihj guided by observations made upon my own ears, I should pre- 

 mise that both are very efficient for hearing ; but that they differ 

 from each other in the important particular that the faucial orifice 

 * Liebig's Annalen, January 1858. 



