GEOLOGY. 329 



and in the fifth, 113,178 kilogrammes. For several subsequent years the 

 annual product was 403,912 kilogrammes. 



It will be seen how much the silver gain has increased from the first to the 

 second period. It fell short in the third period 415,827 kilogrammes, and 

 increased again in the fourth, 726,779, and in the fifth, 1,004,470 kilogrammes. 

 The increase in the yield of silver during the sixth period was only 9,120 kilo- 

 grammes. 



The annual value of the gold and silver extracted during the first period 

 was barely 16,000.000 francs. It increased hi the second period to 130,500,000, 

 and in the third to 152.500.000 francs, while it nearly doubled from 1825 till 

 1848 increasing as it did to 280,000,000. In the next period it more than 

 doubled, amounting to 601,000,000 francs, and in the last four years it has 

 increased nearly 150 per cent., and now amounts to 1,592,631,651 francs, or 

 8318,526,350. 



The following table will show the amount of the precious metals hitherto 

 extracted from the different countries on the globe : 



Gold. Silver Tohil value. 



Kiln. Kilo. Francs. 



Europe 929,444 23,896,106 8,414,000,000 



Asia 7,058,938 72,866,362 42,708,000,000 



Africa 2,104,694 1,259,220 7,292,060,000 



America 3.599,295 146,591,473 41,646,000,000 



Australia 762,282 .... 2,625,000,000 



So that the total amount of gold and silver extracted in America up to the 

 close of the year 1855, is only about $20,000,000 less than the entire pro- 

 duce of the Asiatic mines since the beginning of the world, while it is already 

 more than double the entire past yield of all the mines of Europe. Africa, 

 and Australia put together. 



Gold Product of tlie Quartz Milling of California for 1855. A late report 

 of Dr. Trask, State Geologist of California, gives the whole number of mines 

 now in operation as 52. Eleven quartz mines produced in 1854, $777,790 ; 

 eighteen produced in 1855, $2.239,161. Total in two years, $3.016,951. Of 

 some other mines he had obtained the product confidentially, and estimates 

 that the aggregate products of the whole fifty-two would fall but little short 

 of six millions. 



ON THE FORMATION OF CAXXEL COAL. 



The following is an abstract of a paper communicated to the American 

 Association, by Dr. Xewberry of Ohio, on the origin of. cannel coal : 



These coals, as a class, compared with ordinary bituminous coals, are cha- 

 racterized by greater homogeneity of physical structure and chemical compo- 

 sition, having a more laminated and slaty fracture impure specimens, con- 

 choidal across the plane of stratification contain more earthy and more vola- 

 tile matter (and of course less fixed carbon), and the gases which they evolve 

 have a higher illuminating power. The fossils which they contain are either 

 aquatic, or exhibit marks of the action of w r ater. The origin of these differ- 

 ences between cannel and common bituminous coals has been the subject of 

 considerable diversity of opinion among geologists, the peculiar characteristics 



