latter being held in place by interior stay-plates spaced about three feet centres. The main object in turning the flanges inward is to enable the column better to resist impact from heavily loaded vehicles.

The most satisfactory section for columns located on private property consists of four Z bars and a web plate.

EXPANSION JOINT.

The author's ideal expansion pocket is described very fully by both text and drawings in his paper on Elevated Railroads, to which the reader is referred.

PROPER DISTANCE BETWEEN EXPANSION POINTS.

With columns fixed at both top and bottom, as the author recommends, the proper distance between expansion points is about one hundred and fifty feet.

SUPERELEVATION ON CURVES.

Superelevation of the outer rail can be obtained by varying the heights of the stringers, by putting a wooden shim on the outer stringer, by using bevelled ties, or by spiking a shim to each tie. The last two methods are generally preferable, but the second one can occasionally be used to advantage, while the first one would give unnecessary trouble in the shops. It will generally suffice to employ only three bevels for ties, viz., one, two, and three inches in five feet. Such bevels will not, it is true, afford the theoretical superelevation required for the maximum speed on sharp curves; but it must be remembered that it is difficult to maintain high speed on sharp curves, hence the compromise between theory and practice.

FAULTS IN EXISTING ELEVATED RAILROADS.

In concluding his before-mentioned paper, the author made a list of the principal faulty details in existing elevated rail-