390 Scientific Intelligence. 
country should entertain the idea that the surface rocks are everywhere 
decomposed, and that there is no erratic formation or drift here. But 
upon close examination it is easy to see that, while the decomposed rocks 
consist of the small particles of the primitive rocks, which they repre- 
sent, with their veins and all other characteristic features, there is not a 
; while the superincumbent 
indistinct stratification characteristic of the decomposed metamorphic 
rocks below it, nor any of the decomposed veins, but is full of variou 
kinds of boulders of different dimensions. The boulders have not yet 
os on the Parahyba, where iron mines are worked in a rock 
characteristics to northern drift, but no trace has been found of g acial 
action, properly speaking, such as polished surfaces, scratches and furrows. 
e decomposition of the surface rocks to the extent to which it takes 
there are any rocks left in their primitive condition. 
4, Mining Statistics of Great Britain for 1864.— 
Produce of mines. 
Coal, ~ . « - 92,787,873 tons. 
Tron ore, < - - - 10,064,890 “ 
Pig iron, - . - “ - 4,767,951 
Copper ore, - « = “ 214,604 “ 
Metallic copper, —- - - - 13,302. “ 
Lead ore, —- “ “ i 94,433 “ 
Metallic lead, ——- - - - 91,283 “ 
Silver (from lead ore), - - 641,088 ounces. 
Zine ores (nearly all sulphuret), — - - 15,407 tons. 
lic zine, - - - - - 4,040 “ 
_ Iron pyrites (for sulphuric acid and soda works), 94,458 “ 
Tin ore, - obs y mo ASCE 
Metallic tin, es : “ - 10,108 “ 
Gold (from Merionethshire),  - e - 2,887 ounces. 
___ The gross value of the above mineral products was 39,979.837/. There 
were 2,351,342 tons of coal taken to London in 1864 and 1,786,713 tons 
in 1863. Eight and a half millions of tons of coal were exported 12 
1864, and nearly half a million of tons of iron.—Athen., Aug. 19. 
