104 Dr Brewster on a Method of producing aji intense heai 



During the first period the admissions were unlimited. 



During the second partially limited. 



During the last a particular certificate is required from the 

 minister and churchwardens, stating that the child was de- 

 serted and in danger of perishing. 



J. FfNLAY. 



Foundling Hospital, 

 September 26, J 827. 



Art. XIV. — Notice respecting a Method of producing an in- 

 tense heat from Gas for various purposes in the A7'ts.* By 

 David Brewster, LL.D., F. R. S. L. and E. 



Having been occupied for many years in the examination of 

 flames of different colours, with the view of obtaining one per- 

 fectly homogeneous for microscopical purposes, I succeeded 

 in constructing a monochromatic lamp, by which a yellow flame 

 of considerable intensity was produced. In this lamp, which 

 was submitted to the Royal Society of Edinburgh in April 

 1822, I connected with the top of the burner a frame of wire 

 gauze, which, by moving vertically round a hinge, or by a 

 motion to one side, could be placed in a horizontal position 

 above the sponge wick. As soon as it had become red hot, 

 it was made to descend into contact with the sponge, when it 

 converted the alcohol rapidly into vapour, and produced an 

 abundant discharge of yellow light. 



In the beginning of this winter when I lighted my house 

 with oil gas, I was desirous of examining the modifications 

 which the flame of the gas experienced when burned through 

 wire gauze. For this purpose, I took the wire gauze frame 

 of the monochromatic lamp, and having fixed it about two in- 

 ches above a single jet burner, I found that it burned with 

 much agitation, but with almost no light. The inner flame 

 was of a bhiish green colour, and the outer one of a pale blue, 

 slightly tinged with red, which always became of a most beau- 

 tiful homogeneous yellow when any body placed in it became 



• Head before tlie Society of Arts, February 21st 1826. 



