366 Scientific Intelligence. [Aug. 



" There is indubitable evidence, that these mines were known and worked by 

 the aboriginal inhabitants, or some other people, at a remote period. Many pieces 

 of machinery, which were used for this purpose, have been found. Among them 

 are several crucibles of earthen-ware, surpassing in durability the best Hessian 

 crucibles." 



We have extracted the substance of the above notice from " The American 

 Almanac and Repository of Useful Knowledge, for the year 1832 ;" — a small octavo 

 volume, which puts to shame all the almanacks of our own country, with the 

 exception of that published under the auspices of the Society for promoting Useful 

 Knowledge, by the immense mass of information, calendral, statistical, and physi- 

 cal, which it contains, as well as by the method of its arrangement and the neat- 

 ness of its execution. 



2. — Analysis of the Copper Ores of Cuba, in the Cerco of Villa Clara. By Don Ra- 

 mon de la Sagra. 



The specimens produced belong to the class called green copper (cobres verdes), 

 or the carbonate of copper of mineralogists. Some pieces have an earthy appear- 

 ance, and are soft, friable, and of a whitish-green colour, like certain copper ores 

 of Rio Tinto, in Spain, commonly called " verde de montana." Others are more 

 compact, of a sea green, and sometimes a metallic grey. The oxide of iron with 

 which it is combined is very perceptible to the eye. In order to separate it, I 

 pounded specimens of both descriptions of ore, then distilled and calcined two 

 grammes of each, to ascertain the quantity of water and of carbonic acid, and 

 dissolved the mass in boiling nitric acid : after concentrating the solution, filtering 

 it, washing the residuum, and mixing together the water employed in the washing, 

 I obtained 65 centigrams of precipitate from one mineral, and 38 from the other, 

 by means of liquid ammonia. These quantities of ammoniate of iron correspond- 

 ing to 32 and 18 centigrams of metal respectively, or 16 centesimals of iron from 

 the former, and 9 from the latter. The whole contents being, 



1st Specimen. 



2nd Specimen. 



Green copper, earthy ore. 



Sub-carbonate of copper, ) 

 (hydrated.) J 

 Oxide of iron, 



Green copper, compact ore. 



a . , Sub-carbonate of copper, ] c ~ „ 

 64 5 (hydrated.) FF ) . 56 5 



22 5 Oxide of iron, 13 "0 



Silex and earthy residuum, 



13 Earthy residuum, 30 5 



100 100 



3. Coal from the district of Guanah, in the island of Cuba, analysed by Don 



Ramon de la Sagra. 



Texture laminar, of a bright lustre, like the best coal of England — fracture cubi- 

 cal — specific gravity 1.18. 



CONTENTS. 



Carbon or combustible matter of coke, . . . . 60 



Betun mineral, (Tar,) .. .. ..20 



Water, .. ., ..4 



Incombustible ashes, ,-. .. ,. ..12 



Gas, .. .. .. ..4 



100 



