6 Memoir of M. D' Aubuisson de Voisins. 



and improving the legislation relating to the mines in France. 

 M. D'Aubuisson had given, and always afterwards continued 

 to give, particular attention to these legislative considera- 

 tions. Accordingly, the administration of mines did not fail 

 to profit by his knowledge in many circumstances, and par- 

 ticularly in the preparation of the great law on mines in 

 1810. In these early memoirs of which we now speak, he 

 advocated strongly the adoption of certain principles which 

 have since acquired the force of law in France, for example, 

 that of a complete separation between the proprietorship of 

 the mines and that of the surface of the ground. 



From 1801 to 1802 M. D'Aubuisson was occupied with a 

 work of a more permanent character, which he published in 

 three volumes, on the Mines of Freiberg.* This was a work 

 containing much more than its modest title promised ; for this 

 monograph of the Mines of Saxony is conceived according to 

 so extensive a plan, that it seems rather a general treatise on 

 the Art of Mining than a particular description. The author, 

 in reality, passes in successive review the working of mines 

 among the ancients, the classification and general disposition 

 of metalliferous masses according to Werner's viewS; on which 

 little had then been written; then all the technical generalities 

 respecting the woi-king of metalliferous mines, comprehending 

 the methods of cai'riage and ventilation, sinking of shafts, 

 wood-work and masonry, hydraulic moving powers, the pre- 

 paration of minerals ; next the topography, history, and sta- 

 tistics of the mines of Freiberg taken collectively, the distri- 

 bution of all their moving water, their administration ; and, 

 lastly, a particular description of each of them. This publi- 

 cation contained the germ of all the researches, whether 

 mineralogical or hydx'aulic, which have been rendered so in- 

 teresting to science by the works of the latter half of his life. 



He gives an account, in this work, of a numerous series of 

 experiments made by him in the bottom of the mines of 

 Freiberg, on the important question, which was still unsettled, 

 of subterranean temperature. He was, in fact, along with 

 M. Cordier, now General Inspector of Mines, one of the first 



* Des Mines de Freiberg en Saxe et do leur exploitation. Leipsick, 1802. 



