a6o 



APPLIED SCIENCE 



the wheels to leave the line, this hook will prevent the truck 

 from falling. The weight of the two-wheel stiff truck, shown in 

 Fig. 5 (p. 258), with wrought-iron buckets, is 75 Ibs. The weight 

 of the two-wheel pivoted trucks, with wooden bucket, is 63 Ibs. 

 They are both adapted to carry 2 cwt. Fig. 6 (p. 258) shows 

 a one- wheeled truck tested ; the results were not favourable. 

 A special form of bucket must be designed to suit each kind 

 of traffic. Simple iron hooks for sacks will, in many cases, be 

 available, and these hooks can be so contrived that on being 

 .struck they will drop the sack. 



FIG. 8. 



FIG. 9. 



The first type of locomotive which was tried on a large scale is 

 shown in Figs. 8 and 9. The motor lies nearly horizontally across 

 the line, and is connected by a form of frictional gearing, which 

 I term ' right angle nest gearing,' with the edge of a bicycle wheel, 

 W. The shaft of the bicycle has on it two discs, B B, one of 

 which is fixed on the shaft, while the other can slide longitu- 

 dinally on the shaft. These two discs are pressed together by a 

 spring, D. Their edges bear on the horizontal gripping rollers, 

 A and A, which seize the line. These rollers are supported in 

 such a way as to be free to come together under the pressure of 



