This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1891 Excerpt: ...the Author has been the Engineer throughout. The communication is accompanied by four photographs and a plate, from the latter of which the Figs, in the text have been prepared. APPENDIX. Concrete In The Superstructure. The concrete used in the superstructure above the reef deposited out oi water was composed of 3 parts broken slag, J of gravel, 1 of sand, and 1 of cement (see the Table below). All these materials were measured separately in a dry state before being mixed. Large lumps of slag were added to, and incorporated with, the concrete after it was deposited in place, to the extent of about one-sixth of the whole mass. The Author found in practice that with these proportions he obtained the utmost quantity of finished concrete--having a matrix consisting of equal parts of...