Of the Light manifested in Combustion, 225 



now lighted in this manner ; but, if I am not much mis- 

 taken, this illuminator will soon give place to another 

 much more simple in its construction, more econom- 

 ical, and which must produce a much finer effect. 



Since I have become better acquainted with the 

 light which accompanies the combustion of inflam- 

 mable substances, I have found means by a very simple 

 contrivance to increase its intensity in a centre of illu- 

 mination, almost without limitation. 



I lately caused a lamp to be constructed of a very 

 simple form, which, with four flat or ribbon wicks, each 

 one inch and six tenths English measure in width, 

 placed vertically, one by the side of the other, at the 

 distance of about two tenths of an inch, and so sepa- 

 rated as to let the air come up between them, gives 

 more light than six Argand lamps burning with their 

 usual brilliancy. 



I have often measured the intensity of its light, and 

 have never found it to be less than 3800° ; and in sev- 

 eral experiments made in the presence of Professor 

 Pictet and M. Micheli of Geneva, and of M. Charles 

 and M. Gay-Lussac, members of the Institute, it was 

 found to give 4000° of light, equal to that of 40 wax 

 candles of the best kind, all burning together with their 

 greatest brilliancy. 



But in an experiment made at my country house at 

 Auteuil, on the first of November, 181 1, in the pres- 

 ence of M. Russell, Charge d' Affaires of the United 

 States (who takes this paper to England), the result 

 was still more extraordinary. 



Some little alterations having been made in the 

 manner of trimming and arranging the lamp, it fur- 

 nished no less than 5250° of light, more than that of 



VOL. IV. 15 



