1818.] Jean Claude Delamet/ierie. f 



combustible non-metallic bodies, combustible metallic bodies, 

 acids, alkalies, earths, salts, volcanic substances, and fossils! 

 It has been already observed that he disapproved of the plan of 

 making crystalline forms the basis of a mineralogical system : 

 this he regarded as one only among other properties which ought 

 to be employed for this purpose. 



His most singular opinions were those on organized bodies : 

 he supposed that they were originally produced by the crystalli- 

 zation of their seed ; that their vital powers depend upon Gal- 

 vanism, which is evolved by the superposition of alternate strata 

 of medullary and muscular parts ; that there is a strict analogy 

 between animals and vegetables, both in their structure and func- 

 tions \ and that there is no part or property in one of these 

 classes to which a corresponding part or function may not be 

 demonstrated in the other. As his mineralogy is the best, so it 

 may be asserted that his physiology is the worst part of his 

 works; it abounds the most with mere speculation and false 

 analogies, and is the least supported by absolute facts or correct 

 deductions. 



We may sum up our remarks upon the character of Delame- 

 therie by saying, that he possessed many valuable qualities, both 

 moral and intellectual, but that, along with these, he had some 

 natural defects of temper and disposition, which were unfortu- 

 nately fostered by his acquired habits, so as, in a considerable 

 degree, to destroy both his happiness and his utility. Upon the 

 whole he must be regarded as a man more to be respected than 

 esteemed, who, although ardently bent upon the promotion of 

 science, and indefatigable in the pursuit of it, accomplished 

 much less than might have been expected from the same portion 

 of talent and industry, had they been differently directed, and 

 placed under the controul of a better regulated judgment. 



Article II. 



On Phospkuretted Hydrogen, By J. Dalton. 

 (To Dr. Thomson.) 



RESPECTED FRIEND, Manchester, Nov. 16, 1817. 



Having been lately engaged in investigations on the phos- 

 phurets, I had to review the experience of others, as well as my 

 own already published, relating to phusphuretted hydrogen gas, 

 and to make very material corrections and additions. I hasten, 

 therefore, to communicate the facts observed, without going 

 jnto detail of experiments, that others may, if they choose, avail 

 themselves of the train into which 1 have been led. 



