47G ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



mechanical power the heat supplied by the fire to decompose 

 the bicarbonate constantly regenerated. Supposing the gas 

 to act at the temperature of 100 C, the 16 liters of carbole- 

 um necessary per horse-power per hour will be reduced to 

 10 liters. Such an engine requires about 0.3 kilos, of coal 

 per horse-power per hour, w T hile the best constructed steam- 

 engine consumes 1.2 to 0.9 kilos. For ships, the weight of 

 an engine of 100 horse-power, with fuel for 240 hours, will be 

 one fifth less than that of a steam-engine of equal power. 

 And as several parts of a carboleum engine require to be 

 more massive, it will take up less room. Carboleum presents 

 no danger, as it contains no cause of explosion. It is easy 

 to prevent a too abundant accumulation of gas in the en- 

 gine-room, which would render the air unfit for respiration. 

 When not in contact with water the metallic parts of the en- 

 gine are not affected by the carbonic acid. Metals are not 

 permeable by gases at that pressure. In large works the 

 carboleum engine will, it is claimed, in nearly all cases, re- 

 place the steam-engine. In small establishments, and espe- 

 cially where the engines are only worked at intervals and 

 for short periods, the fact of the carboleum being always 

 ready to act at a moment's notice is of great importance ; 

 as, for instance, to drive printing-presses, steam pumps, port- 

 able engines, etc. A carboleum engine is an excellent and 

 economic source of electric li2;ht. M. Beins also recommends 

 the carboleum engines as especially adapted to submarine 

 vessels. 3 A, October 24, 1874. 



REPORT ON THE RECLAMATION OF THE ALLUVIAL BASIN OF 



THE MISSISSIPPI RIVER. 



The report of the commission of engineers appointed to 

 investigate and report a permanent plan for the reclamation 

 of the alluvial basin of the Mississippi River subject to inun- 

 dation has lately been published. This commission, of which 

 General G. K. Warren, of the United States Engineers, was 

 chairman, was appointed under an act of Congress in June, 

 1874, and held its meetings first at Newport and then at 

 Washington, its members visitingr from time to time the lo- 

 calities in the Mississippi Basin requiring particular investi- 

 gation. 



