XLII. C. O. BURGE. 



The explanation of the promoters in defence of this that 

 repairs will only be done at midnight, when there will be 

 no traffic, will hardly satisfy the Board of Trade, who will 

 probably insist on a greater clearance. The trestles are 

 of angle steel 3J square inches sectional area, strongly 

 braced, and are to be tilted on the curves, so as to absorb 

 the centrifugal force due to the speed. To prevent the 

 too quick generation of this force, long transitions or eas- 

 ings of the straights into the curves are to be introduced. 

 As the electrical equipment includes, as already mentioned, 

 one line of 100 tt>s. rails at each side of each line of trestles 

 as feeders, making a total of 840 lbs. of rails per yard, it 

 will be seen that not only the first cost, but the mainten- 

 ance, of the running road will be costly. Owing to there 

 being no sidings or points, disabled or superfluous rolling 

 stock must be transferred from rail to shop, by being lifted 

 off by a crane, and vice versa, or by a dead end off the 

 turntable, one of which is provided at each end of the line, 

 to transfer cars from down to up road or vice versa. 



It will be seen that, unless very great care is taken in 

 the maintenance of this road, dangerous sinuosities will 

 take place in the alignment of the rail. In the ordinary 

 permanent way, a slack or depression, in one rail of say 

 one inch, affects the vehicle passing over it vertically to 

 that same extent and more, and a certain oscillation is set 

 up. But in the case of the trestle, a vertical slack of one 

 inch in the same position, laterally, of the road bed, would 

 slew the bearing rail nearly two inches over and horizon- 

 tally, giving a dangerous lurch to the car, which at the 

 proposed speed, might cause much damage to the structure 

 and possible accident. Of course great care would be 

 taken in the maintenance of such a line, but the possibili- 

 ties of the neglect of it cannot be left out of account. The 

 trestles, sleepers, and rails, not including the feeder rails, 



