VOL. XXXVIII.] PHILOSOPHICAL TRANSACTIONS. 6|3 



through the bed of black-stone, and the two feet coal underneath it, and all 

 that part of the pit, for 4 or 5 feet high, was framed quite round, and very 

 close jointed, so as to repel the damp air, which nevertheless, it was appre- 

 hended, would break out in some other adjoining part, unless it was carried 

 quite off as soon as produced out of the clitfs of the stone ; for which end, a 

 small hollow was left behind the framing, to collect all the damp air into one 

 side of the pit, where a tube, of about 2 inches square, was closely fixed, one 

 end of it into the hollow behind the framing, and the other carried up into the 

 open air, 4 yards above the top of the pit ; and through this tube the said damp 

 air has ever since discharged itself, without being sensibly diminished in its 

 strength, or lessened in its quantity, since it was first opened, which was 2 

 years and Q months before. It is just the same in summer as in winter, and 

 will fill a large bladder in a few seconds, by placing a funnel at the top of the 

 tube, with the small end of it put into the neck of the bladder, and kept close 

 with one's hand. 



The air thus inclosed in the bladder, and tied close, may be carried away, and 

 kept some days, and being afterwards pressed gently through a small pipe into 

 the flame of a candle, will take fire, and burn at the end of th'_^ pipe- as long as 

 the bladder is gently pressed to feed the flame ; and when taken from the candle, 

 after it is so lighted, it will continue burning till there is no more air left in the 

 bladder to supply the flame. 



The air when it comes out at the top of the tube, is as cold as frosty air. It 

 is to be observed that this sort of vapour, or damp air, will not take fire except 

 by flame ; sparks do not afl^ect it, and for that reason it is frequent to use flint 

 and steel in places affected with this sort of damp, which will give a glimmering 

 light, that is a great help to the workmen in difficult cases. 



After the damp air was carried up in a tube, in the manner above described, 

 the pit was no more annoyed with it, but was sunk down very successfully 

 through the several beds of stone and coal, without any other accident, or in- 

 terruption, till it came to the main seam of coals, which is 3 yards thick, and 

 79 fathom deep from the surface; and the said pit being oval, viz. JO feet one 

 way, and 8 the other, it serves both for draining the water by a fire-engine, 

 and also for raising the coals. 



j4n Observation of n Solar Eclipse, May 2, 1733, in the Afternoon. By 

 Mr. George Graham, F.R.S. in Fleet-street, London. N° 429, p- 113. 

 Apparent time. 

 At 5^ 44"" 45' It began. 



6 25 30 The cusps were vertical. 



