16 ANNUAL OF SCIENTIFIC DISCOVERY. 



backwards and forwards within the engine-framing) , to stop it and 

 turn it again ; at thirty-five strokes per minute, or about seven miles 

 per hour, one half its weight ; at seventy-four strokes, or fifteen miles 

 per hour, one and a half times its own weight ; and at twenty miles 

 per hour, four times its weight. 



Mr. Heaton's improvement consists in connecting to an auxiliary 

 crank-pin, a rod of similar length with the piston-rod, on the other end 

 of which is a pulley, working between guide-rods placed on the oppo- 

 site sides of the axle to the cylinders, thus obtaining a counteracting 

 force, preventing concussion. The weight must be equal to the piston 

 and its gearing, so as to make the weight run to the left hand at the 

 same instant the piston goes to the right; the blow to stop the piston, 

 and make it return at each end of the stroke, will be received in the 

 auxiliary crank, instead of in the wheels, producing a neutral point in 

 the centre, and steadiness of motion ; for, when the blow is received 

 in the wheels, the cranks being at right angles, it is communicated 

 through the axle, and gives a twisting motion to the whole framing of 

 the engine ; this being repeated with regularity produces an effect 

 similar to rocking a boat ; this oscillation is found to be greatest 

 when the engine is running most regular for speed, and the piston 

 going the same way with the oscillation of the carriage. The effect 

 of this counteracting motion, when in operation, was so great, that not 

 a tremble could be detected in the model. London Mining Journal, 

 Feb. 2. 



LOCOMOTIVE FOR ANTHRACITE COAL. 



THE Scientific American for Sept. 7 commends very strongly a 

 new locomotive for burning anthracite coal. Its qualities have been 

 tested on the Reading and Hudson River Railroads. A speed of forty 

 miles per hour has been attained, but it is its merit as an engine for 

 burning anthracite coal, without smoke or sparks, that is particularly 

 praiseworthy. The construction of the boiler is peculiar. The fire- 

 box is entirely surrounded with water, and there is a series of horizon- 

 tal copper tubes inserted in a back plate, connected with a back-water 

 chamber at the front end, and these run forward, and are bent up in 

 the fire-box, inserted into and projecting above the crown-plate. In 

 this way there is no waste of heat and no destructive action of the fire 

 upon the tubes. The bent part of the tube allows for the expansion 

 and contraction of the metal, and there is a pump inside, worked by a 

 rod from the engine, to keep up a continual current through the whole 

 boiler. 



NEW TANK LOCOMOTIVE. 



A NEW locomotive of a somewhat novel construction has been placed 

 on the Newcastle and Berwick line. Its principal feature is, that it 

 carries its own supply of coke and water, without the necessity of a 

 tender ; which is done by two tanks, one placed under the footboard 

 and the other under the Ix.-il!:-/. it carries sufficient coke for a run of 



