USEFUL LAMPS. 



761 



A GOOD PETROLEUM LAMP. 



This lamp (fig. 889) burns gazoline without the least odour or danger 

 of explosion. It will serve equally well for petroleum or naphtha. The 

 gazoline used ought to be 660 grammes weight to the litre. 



The central portion of the lamp under consideration has an orifice, A B, 

 which extends through the upper part, and by which the air is admitted to 

 the centre of the flame. Two vertical plates divide the air-current into four 

 portions. The chimney-rest, or gallery, forms with the glass three concentric 

 envelopes, so arranged in stages that the air, when it reaches the plates, 



Fig. 889. A good petroleum lamp. 



may be more and more carried under the flame. The orifices, a b, care- 

 fully regulated, give access to the exterior air. Including the central one, 

 there are four currents of air, of which three strike against the flame. These 

 are very excellent conditions for obtaining perfect combustion., and, con- 

 sequently, there is an entire absence of smell and smoke, while the light is 

 very powerful. 



We may add that any glass will be found suitable to this lamp, and 

 that, in consequence of the separation of the hot air by the currents mentioned, 

 all danger of the glasses breaking from over-heating is avoided. In pro- 



