[P] The correct figures from the Bulletin are 1,577 lb.

[Q] Engineering News, January 7th, 1909, p. 20.

[R] For fuller treatment, see the writer's discussion in Transactions, Am. Soc. C. E., Vol. LXI, p. 46.

[S] See "Tests of Metals," U.S.A., 1905, p. 344.

[T] The Engineering Record, August 17th, 1907.

[U] "The Design of Walls, Bins and Elevators."

[V] Engineering News, September 28th, 1905.

[W] The Engineering Record, June 26th, 1909.

[X] Railroad Age Gazette, March 26th, 1909.

[Y] Engineering News, April 9th, 1896.