File:Cassier's magazine (1911) (14577020529).jpg

Identifier: cassiersmagaz401911newy (find matches)
Title: Cassier's magazine
Year: 1891 (1890s)
Authors:
Subjects: Engineering
Publisher: New York Cassier Magazine Co.
Contributing Library: Smithsonian Libraries
Digitizing Sponsor: Smithsonian Libraries

View Book Page: Book Viewer
About This Book: Catalog Entry
View All Images: All Images From Book
Click here to view book online to see this illustration in context in a browseable online version of this book.

Text Appearing Before Image:
found, however,that the circular shaft is more quicklyand economically constructed — atleast in shale. Excavation at thebottom and concreting the walls goon simultaneously. There is a plat-form from which the concreting isdone. The muck buckets, going upand down, pass through its centre.To prevent injury to the lining, guideropes held in place by weights areemployed in case the lining has to becarried on in the immediate vicinityof the bottom. But little temporarysupport is used, and the saving dueto this is estimated as enough tocover the cost of the concreting. In joining the permanent shaft tothe horizontal section at the bottoma curve is used. This is an expen-sive form, but is thought to pay well,because it eliminates some of thefriction which would otherwise occurat the elbow. It has seemed desirable to have theheads of permanent shafts in rock.But this has not always been possi-ble. In these cases the heavy siphonor pumping chamber will have to rest THE CATSKILL AQUEDUCT 329
Text Appearing After Image:
HUDSON RIVER DIVISION, FOUNDRY BROOK SIPHON SHOWING 9^-FOOT STEEL PIPE ANDCONCRETE SUPPORTING BLOCKS on a different foundation. The ideais to line and grout the earth shaftso as to eliminate settlement. Thecross-sections of the constructionshafts have been made small, largelybecause the amount of material to beremoved is not great nor the raterapid. It is estimated that only 7cubic yards per hour is all that willhave to be handled by two cages.Do the pressure tunnels require drainage? The answer seems doubt-ful. Some time it may seem desir-able to get the water out of thesiphon. But no one knows when thisneed will arise nor what will be theurgency. However, as the need maycome, drainage plants are to be pro-vided at a cost of less than $1,000,-000. The construction of the steel si-phons is much more simple than that 33° CASSIERS MAGAZINE of the pressure tunnel. The internalpressures are moderate, and thereare no external ones. There are novertical shafts, nor any considerableexcavati

Note About Images