in Fluids. 241 



lieve, never even been called in question, may be attrib- 

 uted the little progress that has been made in the in- 

 vestigation of the science of Heat, a science, assuredly, 

 of the utmost importance to mankind ! 



Under the influence of this opinion I, many years 

 ago, began my experiments on Heat ; and had not an 

 accidental discovery drawn my attention with irresistible 

 force and fixed it on the subject, I probably never should 

 have entertained a doubt of the free passage of Heat 

 through air ; and even after I had found reason to con- 

 clude, from the results of experiments which to me 

 appeared to be perfectly decisive, that air is a non-conduc- 

 tor of Heat, or that Heat cannot pass through it with- 

 out being transported by its particles, which, in this 

 process, act individually or independently of each other; 

 yet, so far from pursuing the subject and contriving ex- 

 periments to ascertain the manner in which Heat is com- 

 municated in other bodies, I was not sufficiently awak- 

 ened to suspect it to be even possible that this quality 

 could extend farther than to elastic Fluids. 



With regard to liquids, so entirely persuaded was I 

 that Heat could pass freely in them in all directions, that 

 I was perfectly blinded by this prepossession, and ren- 

 dered incapable of seeing the most striking and most 

 evident proofs of the fallacy of this opinion. 



I have already given an account, in one of my late 

 publications (Essay on the Management of Fire and 

 the Economy of Fuel), of the manner in which I was 

 led to discover that steam and flame are non-conductors of 

 Heat. I shall now lay before the public an account of a 

 number of experiments I have lately made, which seem 

 to show that water -, and probably all other liquids, and 

 Fluids of every kind, possess the same property. That 



VOL. I. 1 6 



