﻿392 Prof. R. Bunsen's Calorimetric Researches. 



tical position as regards that line of magnetic force which, if left 

 to itself, it would accord with. 



The writer desires to express a hope that, in those respects in 

 which his opinions may appear heterodox to commonly received 

 theories, it may be remembered that he puts them forth only 

 as forming a possible basis on which his experiments might 

 be built up. The conclusions at which the investigator may 

 ultimately arrive may be diametrically opposed to those on which 

 his present assumptions rest. Priestley, whose opinion all will 

 recognize as of some value on such matters, gives great encourage- 

 ment to those who do not fear to find their hypotheses fail and 

 their conclusions reversed if by their boldness (it may be auda- 

 city) they have nevertheless forwarded the knowledge of the truth. 



He says, "It is by no means necessary to have just views and 

 a true hypothesis, a priori, in order to make real discoveries. 

 Very lame and imperfect theories are sufficient to suggest useful 

 experiments, which serve to correct those theories and give 

 birth to others more perfect. These, then, occasion further ex- 

 periments, which bring us still nearer to the truth ; and in this 

 method of approximation we must be content to proceed, and 

 we ought to think ourselves happy if in this slow method we 

 make any real progress " *. 



24 St. Peter's Street, E. 



LII. Note on Calorimetric Researches. By R. Bunsen. 

 To the Editors of the Philosophical Magazine and Journal, 

 Gentlemen, April 20, 1871. 



I HAVE just received the enclosed letter from Professor Bun- 

 sen. No man guards more jealously scientific honour than 

 he ; and the following, whilst it explains why the name of Her- 

 schel was not credited with the idea of measuring heat by the 

 increase of volume of melting ice, points out the essential differ- 

 ences between the method proposed by Herschel and that carried 

 out by the illustrious chemist of Heidelberg. 



Tours &c, 



Henry E. Roscoe. 



In a recent Number of PoggendorfFs Annalen Professor An- 

 drews remarks that more than twenty years ago Sir John Herschel 

 proposed an improvement upon Lavoisier and Laplace's ice-calo- 

 rimeter, which, according to Andrews, is in principle and even in 

 several details the same as that which I have employed in my 

 new calorimetric researches (Phil. Mag. S. 4. vol. xli. p. 161). 



* Priestley, ' On Light/ sec. 4, p. 181. 



