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Number of Noiseless Water Heater| 3 | 4 | 5 | 6 | 7 | 8
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Diameter of Steam Pipe, inch | 3/4 | 1 |1-1/4|1-1/2|1-1/2| 2
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[Illustration: FIG. 549.]
_Water Pressure Ejector._ This instrument, Fig. 550, is worked by water
pressure and used to advantage in excavations, cellars, etc., where
water pressure can be had and the required elevation does not exceed
12 feet. It has to be inserted into the water pressure pipe in such
a manner that it will be entirely covered by the water to be raised.
It will raise double the quantity of water which it obtains from the
pressure pipe, _i.e._, it will deliver two gallons for every one it
receives from the pressure pipe.
[Illustration: FIG. 550.]