1824.] Biographical Account of J. G. Gahn. 3 



very, the value and difficulty of which, none but chemists tho- 

 roughly acquainted with the practical department of their science 

 can appreciate. It reflects, however, no little honour on the 

 sagacity of its author ; and it has happened, at a period long 

 subsequent to the time when the composition of this earth, as 

 appearing in the animal kingdom, had become familiar to che- 

 mists, that the same substance, occurring in the mineral king- 

 dom, has been again and again mistaken for a new and simple 

 earth, by analysts of considerable celebrity. 



Just about this time, Scheele had completed his investigation 

 of fluor spar and its acid, and at the conclusion of the treatise 

 which he published on this subject, he informed his readers, 

 that " in addition to the discovery of a new earth, it was also 

 in his power to announce to them that the earth of bones, instead 

 of being an uncompounded substance, is phosphate of lime." 

 The general and ambiguous nature of this allusion to the disco 

 very of Gahn, although wholly unpremeditated on the part of 

 Scheele, was the cause of the credit of it being immediately 

 attributed to him ; especially as Gahn had not then so far com- 

 pleted his experiments as to consider them deserving of being 

 laid before the public in a separate memoir. Nor did such a 

 production of his ever after appear ; for it was one of the cha- 

 racteristics of his comprehensive genius, that he was ever reluc- 

 tant to commit any of his opinions or discoveries in a crude state 

 to the press, and where others imagined that little material 

 remained to be investigated, he saw further, and still experienced 

 a painful sense of imperfection. 



Gahn next succeeded in demonstrating the metallic nature of 

 manganese, which he effected by exposing its oxide along with 

 charcoal powder to an intense heat. This discovery, however, 

 with many others of inferior moment respecting the more 

 recently known metals, was never published by himself, but 

 appeared originally in the chemical dissertations of Bergmann. 

 Nor is there any one trait in the whole character of our chemist 

 more remarkable than that to which we have already alluded, 

 his indifference to celebrity. He rarely, even in private, narrated 

 in an unreserved manner the progress of any of his discoveries, 

 and the person to whom such a communication was made might 

 regard it as the strongest evidence of his full and confiding 

 friendship. The feeling of how much remained to be done, 

 appearing full before his penetrating eye, seems to have over- 

 powered too much the satisfaction and complacency which 

 ought to have resulted from what had been accomplished. And 

 so forcibly did this sense of imperfection oppress him, that a 

 morbid delicacy has in too many instances deprived the world 

 of the results of his unwearied research during the long period 

 of fifty years. In all this time, scarcely any publication of his 

 appeared until he had almost literally obeyed the injunction of 



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