MECHANICS AND USEFUL ARTS. 45 



with its operation, after a short practice. It differs materially from 

 the Prussian military musket and all others loading at the breech ; in 

 the latter the smoke of the powder escapes, but in no instance was 

 there the least appearance of smoke at the breech of Mr. Sears's gun. 

 The explosive power of the gunpowder is so effectively employed as 

 to leave the barrel as clean after firing fifty-four rounds as it was after 

 the first discharge ; and the gun, consequently, is not apt to get clog- 

 ged, as is the case with common muskets. London paper \ Feb. 28. 



MACHINE FOR PURIFYING SUGAR. 



MR. R. A. BROOMAN of London has invented a new machine 

 for depurating sugar and other substances. The principle of the 

 invention is the employment of a centrifugal force, which throws the 

 moisture out and suffers it to escape, while the substance from 

 which the moisture is to be extracted is prevented from flying from 

 the centre. The machine consists generally of a pan mounted on a 

 shaft within a receptacle for the extracted matters. At the lower 

 end of the shaft are two cone-pulleys, connected by a driving-band, to 

 give a gradually accelerated motion to the pans. Loose pulleys are 

 placed on top of the cones, to stop the motion when required, and the 

 cones may be connected to the engine-shaft by spur-gearing to give 

 them a steady motion. There is also a combination of pulleys by 

 which the driving-bands are raised and lowered as required. Within 

 the pan is a loose oag of a peculiar form for unloading, the outer edge 

 being secured to the flange, and the inner one to a ring-nut fitting a 

 screwed spindle, which is secured to the pan-shaft. To unload the con- 

 tents, the nut is held while the spindle turns with the pan, carrying the 

 nut and bag upwards, the centrifugal force of the pan filling the bag. 

 The extracted matters are guided into the bag by a guard as the cen- 

 trifugal force makes them impinge upon it, after which they are de- 

 posited in the receptacle, and, the nut being released, the bag runs 

 down to load again. The rotating drum is double, consisting of an 

 outside and an inside one, and its upper part has a central opening 

 closed by a cover, through which the substances to be purified and 

 dried are introduced, so as to rest upon a false bottom. A wire-cloth 

 is fitted to the interior of the drum, to permit the free escape of moist- 

 ure. The drum rotates on a spindle, and through its centre passes a 

 hollow shaft, for the admission of steam at the top. The channel of 

 this shaft is connected with the space between the drums by a pipe. 

 The substances to be separated are placed in the drum, and the steam 

 turned on, while at the same time a slow rotary motion is given to the 

 cylinder, until all is heated, when the motion is increased, and the 

 moisture is thrown out through the screen by centrifugal force. The 

 moisture is received in the space below the false bottom, and drawn 

 off by a pipe. Water may then be introduced for farther purification, 

 and the process repeated. In some cases it may be advantageous to 

 admit steam to the substance, and then some slight modification of the 

 above arrangement is necessary. 



A London paper states that by this process sugar, which formerly 



