Notice respecting some Experimenls on Alcohol. 1 3 1 



.:iiience has been, that accounts of these experiments have 

 now got into very genera! circulation, and many very con- 

 trary and erroneour ideas have been entertained, not only 

 as to their extent, but even ds to their nature: and it has 

 been imao-ined that a communication lilce the present is 

 the only way to obviate these misconceptions, — miscoa- 

 ceptions wbich I owe as much to you as to myself to re- 

 move. , 



The importance of a method of producing a great ue- 

 oree of cold becomes apparent, when it is considered that 

 ft is at present a very common opinion among chemists, — 

 an opinion founded on a very gener.il analogy. — that all 

 erases may be reduced to the state of liquids by the abstrac- 

 fion of caloric ; and that, bv a further abstraction of caloric, 

 all liquids in their turn may be reduced to the solid state. 

 If this be true, and were we in possessicyi of a method of 

 sufficiently abstracting caloric, all bodies whatever might be 

 reduced to the solid stale. We should thus become ac- 

 quainted with a great number of substances that we have 

 hitherto had no opportunity of examining ; many powerful 

 agents would likely be obtained ; many new and interesting 

 compounds formed ; and much light could not tail to be 

 thrown on the constitution of known substances. 



Directing my attention to this subject, in the summer of 

 1810, a method occurred to me, by which I imaguiL-d a 

 greater degree of cold might be produced than had hitherto 

 been obtained. Although the power of this method ap- 

 peared in theory almost Indefinite, yet it was easy to foresee 

 that in practice many circumstances might at first concur 

 to set limits to its application : from the nature ot these 

 circumstances, however, it was to be expected that some of 

 them might be considerably modified, and many of them 

 might in Time he altogether removed, and thus the practice 

 made in some degree to approximate to the theory. 



At the time this metliod occurred to me, the pressure of 

 my professional avocations did not allow me to prosecute 

 it; but, a.s I anticipated some leisure in the following 

 autumn, I immediately began to provide, at any leisure mo- 

 ments I had, such apparatus as I considertd absolutely 

 necessary, or was most likely to be useful. Tlie Iitilt de- 

 pendence, however, which is to be placed on general rea- 

 soning on sucli subjects, and the apprehension that the 

 method might have been previously tried and louud in- 

 sufficient by others, prevented me from providing any very 

 extensive apjiaratus. 



My first experiment was tried in the following autumn. 

 ■^ 12 'Hie 



