•10 Royal Society. 



tected the principle, leaving to others the comparatively easy 

 task of subsequent addition. 



The true nature of that substance previously named oxymuri- 

 atic acid, with the discovery of a new supporter of combustion ne- 

 gative in comparison with all other substances except oxygen on 

 the galvanic scale. This discovery, like those already noticed^ has 

 impressed a new form on chemical science, and especially it has 

 corrected some too hasty generalizations in the theories and in the 

 nomenclature of that most distinguished chemist who enlightened 

 the world through the medium of a new language. 



To these may be added, on account of its practical utility and 

 the ingenuity of its construction, although on a scale not in any 

 degree commensurate to those of discoveries affecting general prin- 

 ciples or extensive science, — the invention of what has been termed 

 the safety lamp, for guarding against the explosion, in coal mines, 

 of inflammable air. The fact had previously been observed, that 

 flame would not pass through narrow tubes. I have letters from 

 Davy which explain the progress of his thoughts. His first idea 

 was to admit air at the lower surface of the lamp through lubes 

 sufficiently long, and slender in diameter to exclude flame; and to 

 allow the escape of aii- through similar tubes at the top ; surround- 

 ing the sides with glass, talc, or horn, in the usual way. But since 

 internal combustion and explosion cannot be avoided, it is obvious 

 that such coatings must be liable at least to the danger of being 

 scorched or burst. I have a second or a third letter with the fol- 

 lowing query : — Since the length of a tube adequate for resisting 

 flame appears to diminish in some higher ratio than its section, may 

 not the interstices of wire gauze be considered as tubes, and the 

 thickness of the gauze itself as their lengths? — And if so, will not 

 wire gauze, made sufficiently fine, stop the progress of flame and be 

 free from the dangers attached to other transparent substances, from 

 internal explosion ? I need not add that this plan has succeeded. 



1 he protection of copper sheathing on vessels, I have had oc- 

 casion to notice in a former year ; and I shall only repeat, that it 

 forms a most legitimate deduction from the laws of electro-che- 

 mistry ; and that whenever practical difficulties shall be overcome, 

 a doubt can scarcely be entertained of its ultimate success. 



Such is the imperfect sketch that I have presumed to give of 

 Sir Humphry Davy, omitting much of importance in his high cha- 

 racter of an inventive philosopher, by which he has added to the 

 credit, to the honour, and to the fame, of this most distinguished 

 Society, by which be has diffused a lustre on the province which 

 gave him birth and on the entire nation to which he belonged. 



Some short account of so extraordinary a man in his early years, 

 may however be expected from the only member of the Society 

 who has witnessed them. 



In infancy his mind ran upon romance. He had probably read 

 or heard some tales of chivalry. His ardent wish was to issue forth 

 armed cap-a-pie and to clear the world of giants and monsters. At 



school, 



