-. ; 



* , 



290 OBSERVATIONS UPON THE CADMIA 



observations on this subject are very full ; these and 

 a few short notes by Messrs. Collet Descotils, Heron 

 de Villefosse and Berthier in the " Journal and 

 Annales des Mines/' are the only notices of it 1 have 

 ever met with ; I have sought in vain for a mention 

 of it hi English works. The cadmia of Belgium is a 

 new and rare metallurgical product, which is formed 

 in iron furnaces about five or six feet below their ori- 

 fice, and immediately under the charge ; it there 

 forms an annular disk or ring, which increases con- 

 tinually in thickness, and which, if not removed, 

 would choke the furnace ; it forms in the Belgian 

 furnaces, according to Mr. Bouesuel, " a ring of 

 about sixteen inches in height, offering in the profile 

 or vertical section, a curvilineal triangle, the base of 

 which rests upon the sides of the furnace ; and the 

 apex, which corresponds with its greatest breadth, 

 is but little distant from the lower part of the rins;. 

 so that the triangle appears in some cases almost 

 rectangular." I have seen a piece found at Ancram, 

 which presented tolerably well the above described 

 characters, and corresponded exactly with Mr.Boues- 

 nel 9 s description ; like the European, it was found 

 in tabular masses, presenting in many cases a distinct 

 slaty structure. The substance has often a striped 

 aspect; its colour is grayish, inclining to yellow, 

 green or black. The specific gravity of the European 

 is 5. 25, of the American 4. 1)2 ; this difference is not 

 very great, and may in part be accounted for, by the 

 fact that the former contains a small quantity of lead* 

 Which varies from 2. 4 to 6. per 100. 0. 



