122 
Report on the Trials of Sheaf-Binders 
fixed brackets, in which the main axle is guided, revolve two 
drums, one of which serves as a winding drum and the other 
as a brake ; to these are secured the spur-wheels with which the 
driving-pinions gear the shaft which carries them, having also 
the differential machinery on it. 
The connection between the driving-drum, which also forms 
the brake, and the road-wheels is as follows : — A loose ring is 
carried on the inside of each road-wheel by two driving-lugs 
cast on to it, and held in recesses in the driving-drum in such 
manner that it is free to move radially in the line of the lugs, as 
far as the play of the spring requires. By this arrangement 
the vertical motion of the axle caused by the play of the springs 
does not in any way interfere with the gearing. Many attempts 
have been made to place a traction engine on springs ; hitherto 
interference more or less with the gearing has proved the 
difficulty which Messrs. Fowler and Co. have apparently over- 
come by this ingenious mechanism. How long the parts sub- 
ject to friction will last is a question for practical experience. 
The engine was sent out for trial, made to run over a number 
of deals, which showed very plainly the action of the springs, 
and the consequent saving of wear and tear to the engine ; next 
over big stones, and then across the downs over rough land. The 
steadiness of the body and the compression of the springs were 
points that could not be gainsaid. According to Mr. Greg's 
statement, the additional cost of the springs would be about 60Z., 
but no extra price is put upon the engine, which stands as 
before at 510Z. 
The Savile Street Foundry and Engineering Company, Sheffield, 
exhibited Hall's improved Bone Mill, No. 5600. The ingenious 
arrangement for reducing the speed of the rollers by differential 
gear, combined with an improved friction-break, deserves a 
short notice. The belt-speed, which is rather high, is thus 
reduced 20 to 1. In a strong iron frame is mounted a pair of 
toothed rollers (having separate rings of teeth of wrought iron, 
machine cut, and case-hardened), geared together by expanding- 
gear. One roll, by a screw arrangement, is movable, so as to 
be set closer or wider, according to the materials to be crushed 
or the results desired. These rollers revolve in bearings, the 
spindles being hollow. Through one of these spindles, a high- 
speed shaft with a 4-feet fly-wheel thereon, driven by friction 
through a break-strap, rotates, having forged or keyed thereon 
an eccentric, upon which is mounted loosely an external toothed- 
wheel with 19 teeth, a wrought-iron tail-lever preventing this 
wheel from turning round. On the spindle of the roller is 
keyed an internal toothed wheel, having 20 teeth, into which, 
the aforesaid external toothed-wheel gears. The amount of 
