File:Pacific service magazine (1918) (14596672909).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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, made use ofhis sun-and-planet motion until the saw the remedy in keeping the cylinder patent on the crank expired,as hot as the steam that entered it. With In 1782 Watt patented two further im- provements of the first importance, bothof which he had invented some yearsbefore. One was the use of double ac-tion, that is, the application of steamand vacuum to both sides of the pistonalternately. The other was the use ofsteam expansively within the cylindernow unversally used in all steam engines.Watt also connected the valve gearingto the walking beam of the engine and installed a throt- tling governor, belt driven from the main shaft. I have used this history ofthe steam engine leading upto the generation of steam, asmost of the earlier steam en-gines were a combination en-gine and boiler, that is, thesteam was generated in someof them within the powercylinder itself. Steam in the earlier days was known as water vapor and today is known by the chemist Fig. 6 as H2O plus heat, that is.
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_!_.!_ Pacific Service Magazine 103 hydrogen two parts, oxygen one part.This exists in three forms, ice, water andsteam. Below 32 degrees F. H2O assumesa solid form known as ice. Above 32degrees F. (at atmospheric pressure, thatis, 14.7 pounds at sea level, barometer 30)to 212 degrees F., it exists as water. Withthe same atmospheric condition, above212 degrees F. it changes from a solidform, known as water, into steam. If we place one pound of water in acylinder at 32 degrees F. or slightlyabove, keeping the cylinder absolutelyvacuum tight, drawing the piston out toa displacement of 3333 cubic feet andmaintaining the temperature at 32 de-grees F., we shall have a steam or vaporpressure of .089 pound. At 212 degrees F., with atmosphericpressure of 14.7 pounds, one pound ofwater turned into steam has a volume of26.36 cubic feet. At 329 degrees F., 101.9 pounds abso-lute pressure, one pound of water evap-orated into steam has a volume of 4.28cubic feet, and with increased tempera-ture an

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