1826.] Rev, Mr. Powell on Radiant Heat. 13 



go before the pleasure of constructing theories, and that fairly 

 to state and appreciate a real difficulty is the first step towards 

 surmounting it. For it is only from a careful compilation of 

 details, from the joint accumulation of seemingly detached 

 experimental results made by various investigators, that we are 

 able to gain a vantage ground, from which we may enlarge the 

 boundaries of the chemical horizon, discover relations previously 

 unknown, and trace connexions between cause and effect before 

 unsuspected. Indeed to one who takes a justly comprehensive 

 view of chemistry, no fact, however apparently anomalous and 

 paradoxical, can be truly said to be detached or unconnected 

 with any part of the science, and to hold any other opinion 

 would be to suppose the laws of nature variable and capricious. 

 It is thus by gradually collecting facts and experiments, which 

 may at first seem to puzzle from apparent diversity, that a care- 

 ful comparison among them may at length discover certain 

 general analogies and relations, which shall guide some happy 

 genius to a system of principles in which the rationale of all 

 that was once anomalous shall be explained. 



It is indeed the humbler task to be the compiler of facts' 

 which are admitted to be beyond one's power even conjecturally 

 to explain, when compared with the efforts of him for whom the 

 former but paves the way, who extracts* principles out of facts, 

 infuses connected relation among previously detached and dis- 

 jointed phenomena, and forms a harmonious system out of 

 confusion. The latter is indeed a godlike flight, which few, save 

 such as Newton or Lavoisier, dare aspire to. But it is a pleasure 

 not unmingled with pride to think that the accumulation of new 

 and interesting facts, while it adds to the general stock of our. 

 present knowledge, may also one day prove the means of lead- 

 ing some one forward on the higher quest. It is hoped, there- 

 fore, the facts detailed in the present notice may prove neither 

 uninteresting now while they seem anomalous, nor useless here- 

 after in guiding some one directly, or by analogy, to give a satis- 

 factory account of the causes w^hich produce them. 



Article II. 



Remarks on some of Mr. Ritchie's Experiments on Radiant 

 Heat. By the Rev. B. Powell, MA. FRS. 



(To the Editors of the Annals of Fhilosophy,) 



GENTLEMEN, 



In a paper in the Edinburgh Philosophical Journal, No. 22, 

 p. 281, Mr. Ritchie has given'some experiments which he con- 

 siders as establishing the fact, that radiant heat passes freely 



