, Memoir on Klckel. i63 



individual in a provincial town, uith an equal number of 

 cases, equally weakening our confidence in small-pox ino- 

 culation. In this respect, then, let tlie two inoculations 

 be supposed to stand upon equal grounds. But let the con- 

 sequences of the one be weighed against those of the other, 

 and the scale of vaccination must incalculably preponde- 

 rate. In immediate danger to the individual, in remote 

 mischief to his constitution, the cow-pox has infinitely the 

 advantage. To this let us add, that while with the cow-pox 

 the practitioner, at the worst, injures no one except his pa- 

 tient, with the small-pox ho may deal miserv and destruc- 

 tion amongst his neighbours far bevond the limits of his 

 operating; that in the one lie is continually risking the dis- 

 semination of a loathsome and mortal disease, while in the 

 other he is conducing to the extermination of that pestilence 

 from among mankind. Lett us then turn to common sense, 

 and ask her which she would prefer. 



GioMcestcr, ChAKLES BrANDON TrYE. 



October 6, 1804. 



VII. Memoir on Nickel, -By C. The.vard*. 



J. HOUGH nickel was scarcely known fifty vears ago, it has 

 already been the object of a great many researches; and yet, 

 by a striking contrast, there is no substance, perhaps, whicb 

 has given rise to so many discussions, and respecting which 

 chemists have su much differed. Some, at the head of 

 whom we ougiil to place Cronstedt, to whom the discoverv 

 of it is due ; and Bergman, who first began to studv it witlr 

 care, considered it as a metal of a peculiar nature. 'Othersy- 

 who did iK>t attend enough to experiment, and who were 

 seduced by its magnetic properties^ did not hesitate to be- 

 lieve it to be iron more or less pure, or more or less altered. 

 The former, suffering themselves to be deceived, in particu-' 

 lar, by the blue solution of its oxides in ammonia, have 

 confounded it with copper. The latter, too confident in 

 slight or superficial researches, have seen in its ore only 

 the arsenic and the cobalt, with which it is almost always 

 accompanied, and have taken it for an alioy of these two 

 ftietals. Opinions so different and so singular could not 

 but disappear with time. The interest of the science re 

 quired it; and it was a necessary consequence of the pro- 

 ducts of mineral analysis, formerly uncertain in its progress, 



• From tlie Annates de Ck'tmir, No. 149, 



and 



