Report of the Acushnet Water Board to the City Council (Paperback)

This historic book may have numerous typos, missing text or index. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. 1871. Not illustrated. Excerpt: ... APPENDIX. The review, from which the following extracts have been taken, was prepared by lloswell E. Briggs, Civil Engineer, who was at one time connected with the New Bedford Water Works. Mr. McAlpine thus speaks of it. "I have carefully examined this paper, and fully agree with the author in the statement of the principles which should govern in the construction of Pumping Engines, in the facts stated, and in the arguments advanced in favor of the principles enunciated. I take the liberty of recommending it to the perusal of those engaged in the planning and construction of works of a similar character." The extracts are here published with the belief that they will aid in obtaining a correct knowledge of the Pumping Engine of the New Bedford Water Works. EXTRACTS FROM A REVIEW OF THE McALPINE PUMPING MACHINE. The duty to be performed by a Pumping Machine is peculiar, and differs materially from nearly all the other applications of steam power. The resistance to be overcome is nearly constant, and the power, at all times, must be at least equal to this load. At every change in the direction of the movement of the piston of a water pump (that is, at the end of each stroke), the momentum of the water in and near the pump which has been absorbed, is destroyed, and at the commencement of the succeeding stroke, the power is first exerted to develope the inertia of the water and again set the column in motion. These changes take place in all reciprocating pumps, and a primary object in the arrangement of a Pumping Machine is to reduce the resistance from these changing motions to a minimum. Steam working expansively, meets the requirements of a reciprocating pump exactly. When first admitted into the cylinder, it has a pressure much greater than that due to the weig...