GEOLOGY. 379 



Lead and Silver, 1,431,509 



Zinc Ore, 27,455 



Iron Pyrites, 46,066 



Iron Ore, 5,695,815 



Arsenic, 1,911 



^Nickel and Uranium, 527 



Coals, 16,663,862 



Salt, 553,993 



Barytes, etc., 10,000 



Porcelain, etc., 120.896 



Building Stones 3,042,478 



30,602,322 



Of all these substances, says the report, the quantities obtained in 1856 

 arc larger than those of the preceding years, but of coals the increase is 

 something extraordinary. The money value of coals is now more than half 

 that of all the other mineral substances put together, and the increase in 

 quantity is upwards of tico million tons. The coal produce of last year as 

 compared with the two preceding years, is as follows : 



1854 64,661,401 



1855 64,453,070 



1856 66,645,450 



Of this increase of the raising of coal nearly one half has been wanted for 

 export, while the remainder has been called for by the enormous increase of 

 our iron manufactures and railways. Nearly one-fourth of the whole amount 

 of coal raised in the United Kingdom is the produce of the mines of Dur- 

 ham and Northumberland. Those two counties are being undermined at 

 the rate of fifteen millions of tons per annum, and jet, say geologists, we 

 have no need to fear a supply of coal falling short for some hundreds of 

 years. 



DEEP SEA-SOUNDESTGS. 



In connection with the surveys instituted in behalf of the trans-Atlantic 

 telegraph, some highly-important explorations, by means of deep sea-sound- 

 ings, have been made during the past year by Capt. Berryman, U. S. N., 

 of the surveying steamer Arctic. 



Soundings were made and submarine temperatures observed at depths 

 varying from eight hundred fathoms to three miles. Compared with these 

 results, the observations of others in comparatively shoal water, are of minor 

 interest. In every instance specimens of the bottom were obtained, gene- 

 rally of what appeared a dark blue mud, but which, when examined with a 

 powerful glass, exhibited the same curious microscopic revelations observed 

 in the specimens from the telegraphic plateau. Bat the most curious points 

 were the temperatures of the bottom of the ocean. So imperfect is the 

 apparatus for registering these submarine temperatures, that contradictions 

 will arise, but a constant repetition of experiments has proved that at a 

 depth of three-fourths of a mile and over, there exists a degree of cold un- 

 known on the surface. 



