296 PHILOSOPHIC At, TRANSACTIONS. [aNNO 1739. 



paper, though it were waved all over the ditch, would not set the water on fire. 

 He then had a dam made in the ditch, and the water thrown out, to try whether 

 the steam which arose from the ditch would then take fire, but he found it 

 would not. He still however pursued his experiment, and caused it to be dug 

 deeper ; when at about the depth of half a yard, he found a shelly coal, and 

 the candle being then put down into the hole, the air caught fire, and con- 

 tinued burning. 



Dr. C. observed that there had formerly been coal pits in the same close of 

 ground ; and having got some coal from one of the nearest pits, he distilled it 

 in a retort in an open fire. At first there came over only phlegm, afterwards 

 a black oil, and then also a spirit arose, which he could noways condense, 

 but it forced the luting, or broke the glasses. Once, when it had forced 

 the lute, coming close to it, to try to repair it, he observed that the spirit 

 which issued out caught fire at the flame of the candle, and continued burning 

 with violence as it issued out in a stream, which he blew out, and lighted again, 

 alternately, for several times. He then tried to save some of this spirit, taking 

 a turbinated receiver, and putting a candle to the pipe of the receiver while the 

 spirit rose, he observed that it caught flame, and continued burning at the end 

 of the pipe, though you could not discern what fed the flame : he then blew 

 it out, and lighted it again several times; after which he fixed a bladder, flatted 

 and void of air, to the pipe of the receiver. The oil and phlegm descended 

 into the receiver, but the spirit, still ascending, blew up the bladder. He then 

 filled a good many bladders with it, and might have filled an inconceivable 

 number more ; for the spirit continued to rise for several hours, and filled 

 the bladders almost as fast as a man could have blown them with his mouth ; 

 and yet the quantity of coals he distilled was inconsiderable. 



He kept this spirit in the bladders a considerable time, and endeavoured 

 several ways to condense it, but in vain. And when he wished to amuse his 

 friends, he would take one of these bladders, and pricking a hole with a pin, 

 and compressing gently the bladder near the flame of a candle till it once took 

 fire, it would then continue flaming till all the spirit was compressed out of the 

 bladder. 



But then he found, that this spirit must be kept in good thick bladders, as in 

 those of an ox, or the like ; for if he filled calves bladders with it, it would lose 

 its inflammability in 24 hours, though the bladder became not at all relaxed.* 



An Experiment concerning the nitrous Particles in the Air ; by the same. 



N" 442, p. 26. 

 Dr. C. took a small gally-pot, and ground the top of it very smooth and true, 



* This so called spirit of coals, was inflammable air. 



