14'2 Intelligence and Miscellaneous Articles. 



tartrate of lime produced by the second reaction was added to that 

 obtained by the first, with all the organic substances, and exposed to 

 a fine summer sun at a temperature of 95° to 104° F. and 113° F. 

 The disengagement of gas took place very slowly, and it required 

 six weeks to produce a small quantity of a substance possessing all 

 the properties about to be described. 



It appears from the experiments of M. Nickl^s, that changes ef- 

 fected in tartaric acid by fermentation, may take place in three modes ; 

 if this acid be free or combined with potash, it is converted into acetic 

 and carbonic acids ; if the potash be replaced with lime, the tartaric 

 acid yields carbonic acid, acetic acid and butyric acid (pseudo-acetic 

 acid); and lastly, under circumstances which as yet are undetermined, 

 the tartaric acid is converted into carbonic acid, acetic acid, and a 

 new acid which M. Nickles calls hutyro-acetic acid, it containing the 

 elements both of butyric and acetic acids, and these acids occur 

 among the products of its decomposition. 



On determining the silver of a salt which M. Noellner had sent 

 to M . Nickles, the latter obtained the same result as the former ; 

 when, however, the acid was set free by the decomposition of the 

 salt of lead with sulphuric acid, then saturated with carbonate of 

 ammonia and precipitated by nitrate of silver at a boiling heat, M. 

 Nickles obtained, at first, fine crystals of acetates, and then from the 

 residual solution, magnificent dendritical crystals of butyrate of 

 silver. The separation of the two acids may also be effected by 

 chloride of calcium ; this salt dissolves the acetic acid only, whereas 

 the butyric acid collects it in an oily form on the surface ; M. Nickles 

 states several new facts as to the mode in which a mixture of acetic 

 and butyric acid acts. Thus butyric acid does not precipitate acetate 

 of lead if mixed with a small quantity of acetic acid. The influence of 

 the latter extends yet further; if a mixture of butyric and acetic 

 acids be saturated with oxide of lead, and excess of ammonia be 

 added, small rose-coloured acicular surbasic crystals of butyrate of 

 lead are formed, which owing to a small quantity of interposed ace- 

 tate are soluble in water. This surbasic salt absorbs carbonic acid 

 rapidly from the air. A mixture of acetate and butyrate of barytes 

 is capable of dissolving a large quantity of chloride of lead, but 

 without forming any definite compound. 



Butyro-acetic acid possesses properties which prevent its being 

 considered as a mere mixture of butyric and acetic acids. It was 

 obtained by the decomposition of a salt of lead which had been ex- 

 posed to the air more than two years ; its odour resembles that of a 

 mixture of the two acids, but less pungent ; it is soluble in water, al- 

 cohol and ffither. It is obtained pure bj' decomposing its salt of soda 

 by phosphoric acid ; it then rises to the surface of the liquid in the 

 state of an oily stratum ; its boiling-point is nearly 284° F. When 

 heated with sulphuric acid, it is slightly altered with the evolution of 

 sulphurous acid gas. 



The crude acid yields a liquid which produces with barytes a 

 prismatic compound ; it is very soluble in water, especially when 

 hot, and but slightly soluble in absolute alcohol ; it is perfectly per- 



