This line was originally designed as a " plateway " on the Outram system, but objections were raised to rails with upstanding ledges or flanges FIG.
The stone lid of the coffer was split into four pieces; but the coffer remained perfectly closed, so accurately was the lid fitted into flanges on the sides of the box.
Jessop thus produced what was virtually the flanged wheel of to-day, having the flanges inside the rails,.
Flat-bottomed rails are fastened to the sleepers by hookheaded spikes, the heads of which project over the flanges.
On all the accepted forms there are two or more flanges at the bottom, running lengthwise of the plate and crosswise of the rail; these are requisite to give proper stiffness, and further, as they are forced into the tie by the weight of passing traffic, they help to fix the plate securely in place.