The heat given out by the combustion of gunpowder is 1,145 Fah. The temperature of the flame must be 5,390. The tension of the gases at the moment of explosion does not exceed 4,373 atmospheres, in place of 50,000 or 100,000, at which it has been estimated. The amount of force exerted by one ponnd of gunpowder is 221,240 pounds raised one foot high.—Cosmos.