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Excerpt from Van Nostrands Eclectic Engineering Magazine, Vol. 20: January-June, 1879Sir: In the September number of your Magazine, a Review of the Report upon the Physics and Hydraulics of the Mississippi, by Humphreys and Abbot, appeared over theMoreExcerpt from Van Nostrands Eclectic Engineering Magazine, Vol. 20: January-June, 1879Sir: In the September number of your Magazine, a Review of the Report upon the Physics and Hydraulics of the Mississippi, by Humphreys and Abbot, appeared over the signature of James B. Eads, C.E. He states at the outset that he desires to reach the general intelligent pubic rather than scientific readers. Although the Mississippi report was prepared for professional engineers, and its conclusions will stand or fall by their verdict, I ask space in your Magazine to expose some of the errors of this popular review.Capt. Eads raises two principal issues with our report, each of which will be considered by itself.Relation Between Velocity And Suspended Earthy Matter.The first question at issue is, whether the water of the Mississippi always holds in suspension the maximum amount of earthy matter, which water flowing with that precise velocity is able to support. If yea, then any diminution in the velocity must cause a deposit- and any increase may cause an excavation, provided the bed or banks are of such a nature as to supply suitable material. If nay, then no such results can be rationally predicated.This question of fact - for theory has nothing to do with it - was conclusively decided in the negative by the long series of observations recorded by the Physics and Hydraulics of the Mississippi. Capt. Eads, with various adjectives which add nothing to his argument, denies the truth of this deduction, and asserts that it is based upon fallacies and blunders made by us in discussing our observations. The accuracy of the latter he does not dispute.Our analysis of these observations, stated in brief, consisted in plotting two curves, of which the common abscissas were times- and the ordinates, respectively the mean velocity of the river in feet per second, and the corresponding number of grains of earthy matter held in suspension by one cubic foot representing the average for the whole river. If the latter quantity were a function of the former, the forms of the two curves would exhibit a certain symmetry- This was not the case, the amount of sediment per cubic foot when the river was flowing most rapidly being often no more than at the lowest stage.About the PublisherForgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.comThis book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully- any imperfections that remain are intentionally left to preserve the state of such historical works.