206 A new Theory of Galvanism. 



tains it. The original passage is, '* Hunc lapidem (viz. the be- 

 lemnite) plmimis in locis apud iios quam copiosissime inveni ; at 

 perpetuo in terra rubra ferreii sive ea motlior glela sive saxea sit." 

 Now follows the translation : " This stone is found very abundantly ' 

 in many places among us in a red ferruginous earth, either in 

 softer or more stony masses." 



In one of my Essays I have mentioned the name of Mr. Martin 

 first, and that of Mr. Smith afterwards, to the great displeasure 

 of my commentator, who thinks I should have mentioned the 

 name of Mr. Smith first, and that of Mr. Martin afterwards ; for 

 what reason 1 am utterly at a loss to imagine, unless, because in 

 reading the passage n'iv commentator has overlooked the words 

 " at an early period," as his friend has overlooked the " nt per- 

 petuo." I really feel obliged to one, who, in questioning my 

 fairness, affords so characteristic a specin)en of his own. 



In the same volume 1 have adduced my reasons for doubting 

 the intimate and invariable connexion which has been said to 

 exist between contemporaneous strata and their fossils. Mr. 

 Farey, an advocate for that conaexion, which he maintains was 

 first laid down by Mr. Smith, "does not undertake to prove 

 its correctness ; he contents himself with assuming it. But as 

 the assumption of a contested fact is apt to imply, not the ab- 

 sence of doubt, but the absence of evidence, I am somewhat cu- 

 rious to be informed how far Mr. Farcy's theory on this subject 

 is borne out by his experience. He has examined Derbyshire with 

 very laudable industry; will he take the trouble to mention, what 

 the fossils are, by which he is enabled to distinguish the diflferent 

 limestones in that county, or the diflferent sandstones, or the dif- 

 ferent shales ? There will be time to discuss the originality of 

 the doctrine when its truth is established. If its truth cannot be 

 established, I beg very respectfully to ask Mr. Farey, whether 

 he can hope to exalt the character of his teacher by proving him 

 the first discoverer of that which does not exist? 



I am, sir, your obedient servant, 



G. B. GRHENrtUGH. 



XXXV. A neto Theory of Galvanism, supported by some Expe- 

 riments and Observations made by means of the Calorimolor, 

 a new Galvanic Instrument ; also, a new Mode of decomposing 

 Potash extemporaneously . Read before the Academy of Na- 

 tural Sciences, Philadelphia. By Robert Hare, M.D. Pro- 

 fessor of Chemistry in the Medical Department of I he. Univer- 

 sity of Pennsylvania, and Member of several Learned Societies. 



X Have for some time been of opinion that the principle ex- 

 tricated by the Voltaic pile is a compound of caloric and elec- 

 tricity, 



