Description of an Apparatus for consuming Fire-damp. 2\7 
more, W. of the conflux, upon or even, in the whin, where it 
again disappears, by the over-lieing of Tyne-Lottom limestone, 
which limestone may be traced to the W. up the same Beck, ta 
High Cup Nick, where the stratum becomes abrupt, as we de- 
scend to Dufton, and the whin, basseting underneath, and only 
about eight fathoms thick. It may also be observed at Great 
Rundle Beck, where the principal level commences, and is drove 
upon it, to the mines at Dufton-fell. 
I may further add, that the same great whinstone-bed occurs 
on the river Wear, near the town of Stanhope, in the county of 
Durham; but not so thick as at Caldron Snout. 
I shall endeavour to answer the other queries in my next com- 
munication. 
Iam, sir, 
Your most obedient servant, 
Ganigill, August 26, 1817. WEsrGARTH ForsTER. 
XXXVII. Description of an Apparatus for consuming Fire- 
damp in the Mines without Danger of an Explosion:— 
Apparatus for re-lighting the Miners’ Davy. By Mr, 
J. Murray. 
To Mr. Tilloch. 
Sir, — Tus sketches which accompany this, represent an ap- 
paratus by which the fire-damp may be consumed on the spot, 
in the mine, without fear of explosion; and an appendage to 
light the safe-lamp when extinguished. _ It is presumed that the 
descriptive account will be found sufficiently explanatory, and 
intelligible. If it should be objected to (fig. 1), that its size is 
too great,—it may be observed, that in the Air collieries safe- 
lamps on the principle of the wire-gauze have been used by Mr. 
Taylor three times the size of those constructed by Sir H. Davy. 
I did not find the plan I originally proposed to relight the . 
lamp by any means unequivocal, when tried in the mine. This 
circumstance led to the present invention, 
I am, sir, ; 
Your most humble servant, 
Douglas, Isle of Man, Sep. 3, 1817. J. Murray. 
P.S.—The great increase of intensity which I discovered by 
exposing the Galvanic plates for a few minutes to the action of 
the atmosphere, prior to reimmersion into the cells, I have since 
repeated very often with the same uniform results. I shall be 
glad to see these in your next Number. 
De- 
