The handling of semi-liquids, commercially known as thick stuff, has always been considered more or less of a serious problem, and many designs of mechanism in the form of pumps have been invented for that purpose.

For pumping tar the improved forms of rotary pumps have recently come largely into use. These will be described later under their proper heads. Fig. 212, page 232, Part one, represents a very satisfactory design of plunger pump for handling the heavy stuff alluded to.

The Deane single sugar-house pump is shown in Fig. 452. These are largely used for pumping molasses, syrup, cane-juice, melter-pan products, etc., and are fitted with linings, valves, etc., to best suit the condition of the fluid to be pumped.

The valves are very large and the motion of the pumps is somewhat slower than for water. By removing one set of bolts all the valves are uncovered.

These products of the sugar-house when of a high temperature can be pumped nearly as fast as water; the following list gives the approved proportions of these pumps.

Table.

The Single Magma Pump. The term magma includes any crude mixture, especially of organic matters in the form of a thin paste, it also means “a confection,” hence, the name given to the pump illustrated in Figs. 453 and 454 is very appropriately applied to a sugar-house apparatus. It is designed for pumping various thick heavy mixtures and semi-liquids and for moving massecuite, second and third sugar.

The construction in Fig. 453 is such as to insure strength and certainty of operation; there are no intricate small parts, and the interior is readily accessible. These pumps are made with brass-lined cylinders, or cylinders and fittings entirely of composition when needed to overcome the difficulties appertaining to pumping acidulous and corrosive liquid substances.

The single fly-wheel magma pump as shown in Fig. 454 represents the highest type of machine for this class of work. The steam end is of the plain slide valve pattern. It is fitted with a heavy fly-wheel, perfectly balanced. The admission of steam is regulated by a throttling governor of approved design. The fly-wheel and governor insure a uniform speed of the pump under variations of load—hence the fly-wheel pump does not require adjustment of throttle for every variation in water pressure, as is necessary with direct acting pumps.

The following table applies to the two styles of the magma pumps—with and without the fly-wheel, as the pump ends are the same in both. Attention is called to the number of strokes per minute (thirty) shown in the table as compared with the number of strokes (100 and 125) called for in the previous table. This is caused by the different viscosity of the stuff to be handled by these machines.

Table.