rcfpeBing Heat or Caloric, 159 



guiflied ixom free beat, the do6trine ought to be reje£l<?(l, on 

 the received axiom, that no more caufes (hould be admitted 

 in phyfics than what are true, and fufficient to account for 

 the phaenomena. 



I alfo fucgefled the propriety of philofophers turning their 

 attention to the determining the mafles or vokmies of heat 

 necefTary to produce the various etFe<Sis and changes which 

 that fubftance operates upon bodies, inftead of contenting 

 themfelves with fpeaking of degrees, to which they annex 

 ao correct idea ; and exprefled a hope that, at no very diftant 

 period, this improvement might be expelled in fcience. 



In venturing to call in queftion the truth of the received 

 do6lrines, it was not my intention to depreciate the difco- 

 veries of a Black, a Crauford, a Lavoifier, or a Cavendifh ; 

 men vvhofe memories will be cheriflied, while the world en- 

 dures, by every lover of fcience. Their genius, their per- 

 fevering induflry, their penetrating judgment, firft brought 

 to view thofe luminous fa6ls which muft ferve as the bafis of 

 rill true theory refpe6ling the fubje£ls of which they treated ; 

 and thofe fa6l3 will remain, w^hatever may be the fate of the- 

 ories already eftablifhed, or of others that may fuperfede 

 .4hem. 



But as truths, once eftablifhed, become a common property 

 in fcience, thofe whofe genius would never have difcovered are 

 not debarred the ufe of them. It may alfo be obferved, that 

 the original difcoverers of important fa<St;s have often, in draw- 

 ing their inferences and making their dedu6lions, given an 

 undue weight to coniiderations that were no other way con- 

 -Beded with the fubje6l than by being unfortunately y/z/w^/c^/ 

 over in fonie part of the journey, in which they chanced to 

 he out of the right road ; for who, that firft explores an un- 

 known region, can be expe6t:ed to get on without interrup- 

 tion or impediment? Such accidents, however, have an un- 

 avoidable influence on the mind ; and to exempt any man 

 from their confequences, when they occur, would be tg deny 

 that he is human. 



Thofe who are not aware of the difficulties of this kind 

 with which genius has to encounter, can never rightly appre- 

 ciate the merits of thole who, in fpite of their in§uciice, give 



an 



