Section 86.—TANKS AND CISTERNS.

[1560]. Plan of square tank of ordinary form; formed of cast iron flanged plates and wrought iron tie rods, the joints are either made with rust cement or planed and jointed with tape and red lead.

[1561]. Plan of square tank with rounded angles.

[1562]. Circular tank. No tie rods required.

[1563]. Elliptical tank. Requires tie rods across the flat sides.

[1564]. Polygonal tank. No tie rods required.

[1565]. Elevation of square or polygonal tank.

[1566]. Elevation of cylindrical or circular tank.

[1567] & [1568]. Condensing or cooling tanks. Surface condensers with sloping trays or tubes.

[1569]. Wrought iron tank, usual section, formed of sheets and L irons riveted together.

[1570] & [1571]. Circulating or depositing tanks.

[1572]. Boiler saddle tank.

[1573]. Circulating tank for hot water.

The level of water may be maintained in tanks by either an overflow pipe or notch, or by a ball cock on the supply pipe. Glass water gauges can be fixed outside to show the level of the water inside; and floats are used, attached to a cord and pulleys, for the same purpose. See also [No. 1730].