66 Safety -lamp Controversy. 



lamp of this kind was produced in public on December 5, at New- 

 castle; {three weeks after it was known there that Sir H. Davy 

 had made a safety-lamp with small apertures, and was believed to 

 be safe by the persons w-ho saw it,) because the flame was extin- 

 guished in it by admitting iinmixed fire-damp, or carburetted 

 hydrogen ! which would have been the case had it been a com- 

 mon lantern. 



Having shown tiiat the lamjjs sold by Mr. G. Stevenson in Ja- 

 nuary 1816 have in them no principle of security, it is hardly ne- 

 cessary to prove, that he could not have discovered and applied 

 a principle of security before the middle of October 1815. 



It may, however, be proper to examine some statements that 

 he has made, or that have been made for him. It was said, but 

 not published till September 1816, that be showed a lamp having 

 three capillary tubes to his employer, Mr. Lambert, on November 

 1 7th, and tried it before him with hydrogen ; and Messrs. C. and 

 R. Brandling state for him, that he tried a similar experiment be- 

 fore them November 2^th. There can be no doubt that these 

 trials were conducted as those of December 5th, at Newcastle, by 

 throwing unmixed fire-damp into the lamp, and therefore they 

 can have been of no value ; and it is certain that a light could 

 not be supported, if fed with air bv capillary tubes or by safe tubes 

 of the length and figure of those engraved in his pamphlet* 

 published in 1817; and besides, a fortnight before this period. 

 Sir H. Davy's fact that explosion of fire-damp would not pass 

 through certain small tubes was known at Newcastle, and a week 

 before his paper had been read at the Royal Society. 



Mr. George Stevenson himself asserts, that he tried an experi- 

 ment with a lamp furnished with what he calls a tube and a slider, 

 on October 21, 1815, and that he had tried the lamp with the 

 three tubes November 4th ; but he did not publish this account 

 till September 1816 ; and the Rev. John Hodgson states that he 

 had circulated, about the 2d or 3d of November, manuscript 

 copies of notices of Sir H. Davy's discoveries, which were com- 

 municated to him briefly the 19th of October, and fully the 30th 

 of October 1815, amongst the viewers of the neighbourhood; 

 so that even if it be allowed that Mr. Geo"ge Stevenson began 

 his experiments on capillary tubes the 4th of November, still, at 

 the time, he might have heard of Sir H. Davy's facts respecting 

 them. 



With regard to his experiments on a lamp with a tube and a 

 slider, this apparatus must be regarded as original ; but it never 

 could have been founded upon any idea of safety-tubes or safe 

 apertures, and never could have led to such an idea ; for the 

 Same of a wick placed as his is figured in 1817, round a tube, 



• A Description oi the Safety-lamp, &c. Baldwin, Cradock, and Joy. 



could 



