PROCEEDINGS 1849 -- 1858. 
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occurs principally in the limestone beds, whilst in the latter the 
principal deposits are in gritstone. In the southern area the veins 
generally run from north-west to south-east, whilst in the northern 
districts they are north-east to south-west. The Grassington mines 
yield about two-thirds of the products from the southern fields. The 
operation is of a very uncertain and speculative character ; the best 
lodes have often great lengths of unproductive ground. 
Two elaborate and philosophical papers were communicated 
during the Carly portion of the decade by Mr. W. Sykes "Ward, of 
Leeds, the first on improvements in the galvanometer and on the 
comparative economy of various voltaic arrangements, and the second 
on some phenomena of dyo-magnetism, with experiments. Mr. 
Christopher L. Dresser, of Leeds, explained a new and cheap voltaic 
battery for the production of the electric light. In retorts used for 
the distillation of coal in the manufacture of gas for illumination, 
there is deposited a carbonaceous matter, lining the whole with a 
coatnig varying in thickness from that of writing paper to several 
inches. The deposit consists either of minute scales, like a section 
of a hollow sphere, or thin layers ; the scales are deposited on each 
other until the whole assumes a mammilar appearance, and consists 
of nearly pure carbon. It will bear the most violent heat with very 
little waste, and can be obtained at comparatively trifling cost. If 
cut into sticks about seven inches long, and an inch and an eighth 
in diameter, they may be used in batteries in place of platinum of 
equal size, and the resulting electricity appears to be in every way 
similar and equal in quantity. Mr. Dresser had illuminated his 
garden and a large field with a battery of 90 plates. The difference 
in cost between the carbon and platinum negatives would be as £4 is 
to £60. In a discussion which followed, Mr. Pierceall alluded to the 
great advantage it would be if lighthouses were illuminated by 
electricity. Mr. Ward also commended this application, and speak- 
ing of electricity for use for ordinary purposes in the place of gas, he 
showed the fallacy of supposing that this light, however beautiful, 
would ever supersede ordinary gas for shops or streets. 
At a meeting held at Leeds in 1857, Mr. John Hope Shaw pre- 
siding, two papers were read on the discovery of some fragments of 
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