6S On a Lamp for lighting Coal^mineL 



any parade, or institute any rivalship with regard to it, though 

 I considered, and still consider, the plan in all its extent as pre- 

 ferable to anv that has yet been brought forward. 



I should not, however, have thought it necessary on account 

 t»f these circumstances td have taken any notice of this gentle- 

 man's letter, did I not consider myself called on at the same time 

 to reply to the claim which he has lately advanced, indirectly 

 by thfe medium of Sir H. Davy and Mr. Hodgson (Phil. 

 ^Iag. vol. xlviii. p. 3.)2), and now directly to the invention erf 

 liriy lamp. This he had before brought forward in a provincial 

 tiewspaper; and the best reply I can make, I conceive, to be 

 that which I addressed at the time to the editor of a newspaper 

 here, in winch his letter had been transcribed — a copy of which, 

 as follows, 1 request you will do me the justice of inserting. 



" To the Editor of the Edinburgh Star. — Sir, a letter having 

 appeared in your paper of Friday last, in which a claim is brought 

 forward for the invention of a method of lighting mines, so as to 

 guard against the explosion from the kindling of fire-damp, si- 

 milar, it is said, to that which I lately proposed, and this being 

 accompanied with insinuations that the latter has been derived 

 from the former, which it seems was announced in a book pub- 

 lished some months ago by the author of the letter alluded to-^ 

 I think it necessary, from this latter circumstance particularly, to 

 notice what I should otherwise have passed without observation, 

 and to sav that I have never seen this book to the present mo- 

 ment ; nor, on intjuirv, have I been able to learn that any per- 

 son in Edinburgh has seen it, and that I never heard the most 

 distant notice or hint of the plan mentioned in it, until I read 

 the letter in the newspaper. I further assent most willingly to 

 the demand of its author, of ' siinm ci/ique,' and am anxious 

 that he should have exclusively all the credit that can be derived 

 from his plans. He proposes 'a lavlerii. made air-tl^ht, to be 

 fed thrrmgh aflexille tube hy air exterior to that of the mine, 

 tvith a division in this pipe, or another parallel to it, to promote 

 a proper current to supply the fame , and carry off in circulation 

 the heated air impregnated with carbonic acid gas.' Any one 

 having the slightest knowledge of mines, or acquainted with the 

 principles on which a current of air is established, will at once 

 perceive that this is impracticable and absurd. He proposes also 

 * an air-light lamp, liaving a central tide entering into a vessel of 

 limeivuter, which should be frequently agitated to extract the 

 carbonic acid gas formed,' a proposal which exceeds, if possible, 

 the other in absurdity : though even this falls short of a third 

 suggestion, which the author conceives to be of vast moment, 

 that ^ of a double recurved tube off red to the escape-pipe, having 

 the lower bend interrupted^ and the two ends passing into lime' 



ivateTy 



