File:Pacific service magazine (1918) (14782990452).jpg

Identifier: pacificservicema1019paci (find matches)
Title: Pacific service magazine
Year: 1912 (1910s)
Authors: Pacific Gas and Electric Company
Subjects: Pacific Gas and Electric Company Electric utilities Electrical engineering Public utilities
Publisher: San Francisco : Pacific Gas and Electric Company
Contributing Library: San Francisco Public Library
Digitizing Sponsor: San Francisco Public Library

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re started under it, creatinga pressure rise to or a trifle above thepressure in the main boiler and therebyforcing water into the main boiler. Thecocks at G G are try cocks for determin-ing the height of the water. In 1690 Denys Papin, a Frenchman,who ten years before had inventedthe safetj valve as an adjunct to hisdigester, suggested that the condensa-tion of steam should be employed to makea vacuum under piston previously raisedby the expansion of steam. Papins wasthe earliest cylinder-and-piston steamengine, and his plan of using steam wasthat which afterwards took practicalshape in the atmospheric engine of New-comen. But his scheme was made un-workable by the fact that he proposed touse but one vessel as both boiler andcylinder. A small quantity of water wasplaced at the bottom of a cylinder andheat was applied. When the piston hadarisen the fire was removed, the steamwas allowed to cool, and the piston didwork in its down stroke under thepressure of the atmosphere. After hear-
Text Appearing After Image:
Fig. 3 Pacific Service Magazine 101 ing of Saverys engine in 1705 Papinturned his attention to improving it, anddevised a modified form, as shown in Fig. 5. The displacement chamber, A, was acvlinder with a floating diaphragm or

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