(271 ) (April, 
PROGRESS IN, SCIENCE. 
MINING. 
Some researches on the geology of the mining distri@s of Cornwall, with 
special reference to the formation of mineral veins, have recently been sub- 
mitted to the Geological Society by Mr. John A. Phillips, whose extended 
study of the microscopic structure of Cornish rocks and veinstones, coupled 
with his chemical examination of the rocks, must needs give peculiar weight 
to the conclusions which he has reached. He believes that the vein-fissures 
of the tin- and copper-bearing lodes of Cornwall were the result of forces 
acting subsequently to the solidification of the elvans, but in the same general 
direction as those which gave rise to the eruption of this rock. The fissures 
produced by these forces afterwards became filled with minerals, which were 
deposited by chemical action from waters circulating through them: these 
waters were probably, in some cases, at a high temperature, through contaé& 
with highly-heated rocks at great depths, but in other cases the temperature 
of the circulating waters appears to have been but moderate, and the action 
consequently but slow. It seems impossible to determine to what extent these 
deposits were produced by waters rising from below, or how far they were in- 
fluenced by lateral percolation, but the latter action has probably been 
important. Contact-deposits and stock-works have been formed by analogous 
chemical action, set up either in fissures resulting from the junction of dis- 
similar rocks, or in fractures produced during the upheaval of partially- 
consolidated eruptive masses. England, unlike Germany, has so few expe- 
rienced miners who are at once good chemists, mineralogists, and geologists, 
that such a paper from a man like Mr. Phillips is certainly a rarity, and 
deserves accordingly to be thoughtfully studied by the scientific metal-miner. 
A description of the deposits of phosphorite in North Wales has recently 
been laid before the Geological Society, by Mr. D. C. Davies, of Oswestry. 
The phosphorite bed varies from 10 to 15 inches in thickness, and occurs at 
the top of the Bala limestone over a considerable area, having been found in 
various localities from Llanfyllin to the hills north and west of Dinas Mawddy. 
The bed appears to consist of concretions of various sizes, embedded ina 
black matrix. It is notable that the nodules are coated externally with a thin 
black film of some graphite-like mineral. The concretions contain about 
64 per cent of tribasic phosphate of lime, whilst the average proportion in the 
entire bed—including nodules and matrix—is about 46 per cent, This deposit 
has been worked at certain points, and promises to become an important obje@ 
of exploration. 
It is reported that a very large deposit of phosphate of lime has been disco- 
vered in the island of Amba, in the Caribbean Sea. 
Some interesting relics of ancient mining have been recently brought to 
notice by Prof. Boyd Dawkins, who has discovered—in the old workings near 
Alderley Edge, in Cheshire—a large number of rude stone hammers, similar 
to those which have been found in association with old copper-mines at Lake 
Superior, in Spain, Portugal, and elsewhere. It is difficult to fix the age in 
which these rude mauls and picks were used in Cheshire, but it is probable 
that they go back beyond the range of our history, and may therefore be fairly 
called ‘‘ pre-historic.” They were found on Lord Stanley’s property, where 
the copper-bearing sandstones of the Trias are now worked by the wet-way, 
It appears, however, that some old slags discovered in the neighbourhood were 
not found to contain any copper, and hence it is probable that other metals 
may also have been worked here at a comparatively early date. 
As mining geologists must take a good deal of interest in the deep boring at 
Netherfield, generally known as the Sub-Wealden Exploration, we may men- 
tion that the Committee—after having spent many months in fruitless 
VOL. V. (N.S.) 2M 
