Memoir of M. D'Aubuisson de Voisins. 11 



he was so skilled : he was nominated, in the beginning of 

 1803, coadjutor to the Conservator of the Mineralogical 

 Collections in the School of Mines, in Paris, and specially 

 entrusted with the examination and translation of foreign 

 memoirs. He employed the leisure of this modest place use- 

 fully for himself and for science, engaging for the most part 

 in journeys of observation and study ; with which, on his re- 

 turn, he enriched the principal scientific collections, and par- 

 ticularly the Journal des Mines, where his publications suc- 

 ceeded each other with a remarkable continuity. The Me- 

 moir on the Volcanoes of Auvergne and Vivarais, is of the 

 date of 1804. Nearly at the same time, he published a work 

 of an entirely different kind, Sur les Leves de Plans Souter- 

 rains par la methode des coordonees, a method generally fol- 

 lowed since then, and which he believed he was the first to 

 discover ; but, though in disuse, it had been known in Ger- 

 many since 1772. He likewise published in the Journal of 

 Mines, notices on the Coal-mines of Silesia, on the different 

 Foundriesof Germany, and on the Steam-engines of the Mines 

 of Tarnowitz. In 1805, a memoir appeared on the great 

 Coal-mines of Anzin, in which were interesting and detailed 

 observations (the first which had been printed), on the singu- 

 lar and characteristic contortions, which have given a sort of 

 celebrity in geology to the coal -formation of that country, 

 and on the passage of large subterranean sheets of water, 

 which render it so difficult to penetrate to its rich masses of 

 coal ; a powerful obstacle, in fact, which seems to have been 

 placed there by nature to defend the approaches to it, as 

 formerly the di'agon of the fable was said to have guarded 

 the entrance and the riches of the garden of the Hesperides ; 

 but what obstacle can resist the efforts of that modern Her- 

 cules, steam ? 



In 180G, M. D'Aubuisaon again inserted in the Journal of 

 Mines, the description of a mining operation of the highest 

 interest, that of a bed of galena, near Tarnowitz, in Silesia, 

 a description completed by a work on the metallui-gic treat- 

 ment of this mineral. Among other valuable details in these 

 two memoirs, we find an account of the curious process em- 

 ployed at Tarnowitz to cross a formation of moving sands by 



