380 Imperial Imtttute of Fiance. 



until lately, when a most ingenious paper by Mr. Brande, 

 appeared in the Philosophical Transactions (!81l). Upon 

 the reasonings and experiments of that excellent chemist 

 several ob«ervations were made, aJlofwhi^h lertninated in 

 the i'ollowing conclusion, " that his retulatii.n ot" the 

 grounds of Fabroni's objections to the common opmion, 

 was decisive and complete 3" but it was observed that still 

 a few experiments tending to prove that the connnon opi- 

 nion IS correct, might not be considered superfluous. 



The author then remarked, if the temperature specified 

 bv Fabroni as adequate to the decomposition of wine be 

 really so low as 63, that the legitimate consequence would 

 be directly in contradiction to the opinion which the Flo- 

 rentine ptnlosopher laboured to establish : for in almost all 

 cases of fermentation in the large way, the temperature 

 rises to, and most frequently much above 63. 



Several experiments were then detailed which tended to 

 prove that the alcohol is produced in the process of fer- 

 mentation. A fermentation was conducted which never 

 rose beyond 57 : by peculiar management, the vapour of* 

 alcohol was extricated from this wash, which was capable 

 of catching flame from an ignited body. From another 

 portion of the same wash, the alcohol was separated in the 

 insulated form perfectly pure, very strong, and highly in- 

 flammable. Yet in all these experiments the temperature 

 never rose to CO, which is 3\ degrees below that stated by 

 Fabroni as necessary to the formation of alcohol. 



After detailing the remainder of his experiments, the au- 

 thor stated, that from all these he thought he was war- 

 ranted in concluding " that alcohol is a product of fermen- 

 tation, that it exists ready formed and perfect in fermented 

 liquors, and that it exists in them in a state of very loose 

 combination with water and vegetable matter." 



Mr. Donovan repeated the principal part of his experi- 

 ments before the Society, 



IMPERIAL INSTITUTE OF FRANCE FOR THE TEAR 1S12, 

 DRAWN UP BY M. CUVIER. 



[Continued from p. 316.] 



Botany and Vegetable Physics. 



Most physiologists have long admitted that there is in 

 plants an ascending sap, which proceeds from the roots to 

 llie branches, and contributes to the development of the 

 branches in length; and a descending sap which descends 

 from the leaves to the roots, and to v\ hich some ascribe the 

 chief agency in the development of the wood, and conse- 

 quently in the swelling of the trunk. M. Fe- 



