106 Dr Brewster on a Method of prodiicing an intense heat 



an intense local heat, and in procuring it I have been led to 

 new methods, which I trust will be found of some value in 

 practical science. 



As a very great quantity of heat is carried off by the wire 

 gauze, I endeavoured to produce an explosive mixture of oil 

 gas and atmospheric air above the burner, without the inter- 

 position of any substance whatever. After many fruitless at- 

 tempts, I succeeded in effecting this, but any slight agitation of 

 the air either blew out the exploding gases, or converted them 

 into a regular flame. This defect was too serious to be over- 

 looked, and it required some consideration to remedy it. It 

 occurred to me that if a small flame were permanently kept 

 up about two inches above the burner, it would maintain a con- 

 stant explosion of the mixed gases, independent of any acci- ^ 

 dental agitation of the air, and upon making the experiment, '^^ 

 I found it to exceed my highest expectations. In construct- 

 ing the burner permanently for use, a small gas tube a b c, 

 (Plate II. Fig. 3.) arising from the main tube M N of the gas 

 lamp, should terminate above the burner, and have a short 

 tube d e moveable up and down within it so as to be gas light. 

 This tube d e, closed A e, communicate with the hollow ring 

 fg^ on the inside of which four apertures are perforated in 

 such a manner as to throw their jets of gas to the apex of a 

 cone, of which ^g is the base. When we allow the gas to 

 flow from the burner M, by opening the main cock A, the gas 

 will flow at the tube abed, and issue at the four holes in the 

 ringy^ in very small flames. The size of these flames is re- 

 gulated by the cock b. If the ignited gas were now to issue at M 

 its inflammation will be sustained by the four little subsidiary 

 flames, independent of any agitation of the air. 



Besides the great loss of heat occasioned by the wire gauze, m 

 it has another defect equally injurious. A great quantity of 

 soot collects on its lower side, and this soot is carried up into 

 the flame, by the gas rushing through the meshes. The pu- 

 rity of the flame, which in many experiments is essential, is 

 thus contaminated, and a portion of the heat lost by the igni- 

 tion of the particles. This defect is entirely removed in the 

 method which has been described. 



Having succeeded to this extent with gas issuing under itsj 



