Imperial InsiUute nf France, 65 



Messrs. Clement and Desoimes have invented a very sim- 

 ple method of avoiding it. They surround the vessel which 

 contains thejuice to be evaporated wiih the absorbing mailer; 

 and in this way tiie caloric which is liberated irum the 

 vapour at the moment of absorption returns to the juice 

 which wc are evaporating, and this circulation furnishes 

 ■what the new vapour requires. 



We may employ this process with considerable oeconomy, 

 if we begin by reducing the juice to the state of syrup by 

 means of a ventilator, which is also the invention of 

 Montgolfier, and which Messrs. Clement and Desormes have 

 described in the Annales de Chimie for October 1810. 

 The air pump is applied only when the ventilator no longer 

 produces any effect. 



It is easy to see how useful for domestic purposes, and 

 particularly for the navy and army, is this new art of pre- 

 serving entire alimentary substances, by diminishing their 

 weight, and transporting in a small compass to great di- 

 stances thci fermenlable matter which ought to furnish wine 

 and alcohol. 



The same chemists purpose to apply the evaporation in 

 vacuo to the drying of gunpowder, which will be less dan- 

 gerous than the common method in which fire is employed. 

 They have also devoted their attention to the common 

 process of evaporation bv means of fire, and iiave discovered 

 a method of doubling the effects of a given quantity of 

 combustibles over a liquid, e. g. a saline solutioti. It is 

 only necessary to collect the vapour of a first portion of the 

 liquid, and to force it to pass through a second portion. 

 This vapour, when very much healed, gives off a great 

 portion c»f its caloric to the new liquid which it passes 

 through. 



But of all the arts, that which has reaped the most 

 astonishing advantages from modern discoveVies upon heat 

 and vaporization, has been tliat of the distiller of spirits : 

 the process which we arc about to describe, is merely an 

 imitation of those which have been attended with a small 

 portion only of these advantages. 



This revolution, which ahcadv exercises a great influence 

 over the prosperity of our Soiuliern departments, origmated 

 with the laie Edward Adam, a distiller of Montpelier. 



'Ihe basis of Ins process consists in iicating a great part 

 of the wash to be distilled by the vapour of spirits which 

 rises from the eauldron, and m passing this vapour through 

 a series of vessels partly immersed in cold water, which 

 make it deposit its a(»ueous particles, so thai the spirit 

 \'ol. 41. No. 177. ^"/^ J813, t; of 



