ilS TRANSACTIONS OF THE AMERICAN INSTITUTE. 



found that about two parts of alcohol to one of coal oil produces 

 a good flame. It is a cheaper light than burning fluid, and much 

 less dangerous, if there is any danger at all. If the alcohol Avere 

 entirely consumed, the only effect would be that the lamp would 

 smoke. It is as readily lighted as a burning fluid lamp, and can 

 be carried about without smoking. 



Dr. Stevens suggested that a petticoat burner, placed over the 

 coal oil tube, would increase the brilliancy of the flame by pro- 

 moting a draft of atmospheric air, heated somewhat by the tube, 

 and impinging upon the flame just at the point of its ignition. In 

 order completely to consume the light, carburetted hydi'ogen gas, 

 which is commonly burned in cities, three per cent, of atmospheric 

 air is necessary. With the lighter coal oils, about five per cent, 

 of atmospheric air is necessary to produce complete combustion, 

 and therein consists the philosophy of the chimne3\ Some of the 

 heavier oils require eight per cent, of atmospheric air, and if by 

 any means they can obtain that, they do not require alcohol or 

 any other fluid containing hydrogen. 



Mr. C. W. Smith. — My object is to produce a cheap, convenient 

 and portable light. The attempt at burning coal oil without 

 chimneys have three objections : 1. The smell is disagreeable. 

 2. The moment you lift up one the lamps suddenly, as in going up 

 stairs, the flame goes out. 3. The light is very deeply colored. 

 In all three of these respects I think this lamp is superior. I 

 regard the lamp as entirely safe. I have endeavored to produce 

 an explosion, but have not succeeded yet. Glass is a poor con- 

 ductor of heat, and I do not think enough heat could reach the 

 alcohol in the bottom of the lamp, covered with coal oil, to evap- 

 orate it sufficiently to make it dangerous. It will burn any sort 

 of kerosene, or mixture of kerosene and petroleum. 



Referred, on motion of Mr. Johnson, to the Section on Chemistry. 



AMERICAN GEOLOGY. 



Dr. Stevens. — The importance of the mineral formations of any 

 country can hardly be overrated. A nation without iron and coal 

 within its borders, must be little more than an agricultural 

 region. Steam is now the great motive power of the world, and 

 coal is the great generator of steam. It was coal and the steam 

 engine that enabled England successfully to compete, at one time, 

 with the French empire and almost the whole of Europe. France, 

 with a much larger and finer country, has never been able to 

 compete successfully with England, for the reason that within 



