352 Co7iiroversy respecting Snfety-lampi. 



The regular progress of Sir H's investigations after tins time 

 till he discovered a tissue permeable to tis^/it and air, but \m- 

 permeable to Jlame, may be seen in his publications on the sub- 

 ject. 



In a letter dated from Whitehaven Castle, 20th of September 

 1S16 Sir H. pointed out to me a little book, entitled " Elements 

 of Chemical Science," by J Murrav, Lecturer on Chemistry", 

 dated June 1815, in which there are several hints for construct- 

 ing a lamp upon the princi|jle of a diminished atmosphere. " A 

 lanthorn might be made air tight, and fed through a flexible 

 tube, &c." " A division in the tube, or another parallel to it, 

 would promote a proper current, &c. &c." Mr. Stephenson's 

 first lamp, which dates its origin from October 21, 1815, was 

 upon the same principle ; so was that of Dr. John Murrav, of 

 Edinburgh, announced in November 1815; and that of R. W. 

 Brandling, esq. with the bellows on its top, which appeared soon 

 after. 



From the preceding statement, compared with Mr. Stephen- 

 son's dates (and even taking into the account the anxious two 

 months after " he had embraced the idea,") it is evident he was 

 preceded by Mr, Murray, in the application of one tube, and bv 

 Sir H. Davy, in numerous apertures and tubes above and below, 

 for "admittino the hvdrogen gas, only in such small detached 

 portions, that it would be consumed by combustion." 



I believe Mr. Stephenson to be a very modest and a very in- 

 Cjenious man ; and that the first ideas he had of his lamp were 

 the effect of his own reflections on the subject : but when it is 

 insinuated, as it has been, tliat hints respecting theKillingworth 

 lamp were clandestinely smuggled to Sir H. Davy, which led 

 him to the invention of the wire-gauze safety-lamp, the calumnv 

 upon his character is not to be borne. Tlie scientific world are 

 highly indebted to him for his late discoveries respecting the 

 nature and jiroperties of flame ; and the part of the population 

 of this neighbourhood connected with the coal trade, owe him 

 a mighty debt of gratitude for the successful application of these 

 discoveries, to lighting the coal-mines cheaply and securely. 

 He has, I know, spent a year of great anxiety and labour in the 

 service of the coal-owners; it is, therefore, imj)ossible to sup- 

 press one's indignation, on hearing that doubts respecting his 

 claims to these discoveries should have arisen among that bodv 

 of men, especially when his enemies in the scientific world have 

 been held in silence by their astonishment at the novelty and 

 originality of the invention. 



I cannot conclude this letter without observing that I have 



* This gentleman Las been one of the warmest advocates for Sir II. 

 Davy's lamps. 



not 



