Our analysis agrees, as may be seen, best with that of 

 Walker. According to Professor Liebig'sf arrangement of 

 mineral M'aters, the thermal spring of Bath would belong to 

 the saline waters containing carbonic acid. 



XI. Notices respecting New Books. 



On the Correlation of Physical Forces : being the substance of a Course 

 of Lectures delivered in the London Institution, in the year 1843. 

 ByW. R. Grove, Esq., M.A., F.R.S., Barrister-at-Law. Printed 

 at the request of the Proprietors of the London Institution. London ; 

 Samuel Highley, 32 Fleet Street. 



''r^HIS publication treats of subjects which might have been advan- 

 -*• tageously considered at much greater length ; but it must be 

 acknowledged that in the brief space to which the author has con- 

 fined the announcement of his views and speculations, he has done 

 them no small degree of justice ; it may indeed be questioned 

 whether the opinions broached are not of such a nature as to defy 

 the test of experiment to realise or to refute them. This is certainly 

 the case as far as experiment has yet been carried ; but although we 

 discover great reason for doubting whether the difficulties which 

 beset the subjects may ever be overcome, we discover no cause for 

 despair, seeing that new modes of research and new instruments for 

 carrying them out are of almost daily occurrence. As a proof of 

 this we may cite the author's excellent invention of his well-known 

 and justly- appreciated voltaic battery ; and his still more recent 

 discovery, that water may be decomposed by heat so as to exhibit 

 both its elements in the gaseous form. 



Mr. Grove states tliat "the position which he seeks to establish 

 in this Essay is, that the various imponderable agencies, or the affec- 

 tions of matter which constitute the main objects of experimental 



* Recalculated according to a more correct principle by Walker, 

 t Handworterhuch der Cliemie, Art. ' Analyse der Mineral wasser,' 



F2 



