As to comparative wear, it maybe remarked that one perforated basket will outlast three wire ones.

As to size, sugar baskets vary from 80 inches in diameter by 14 in. depth to 54 by 24.  They are made, however, in England as large as 6 feet in diameter—­a size which can be run only at a comparatively slow speed.

A peculiar complication of basket deserves notice (Pat. 275 874).  It had been noticed that when a charge of magma was put into a centrifugal in one mass, the sugar wall on the side of the basket was apt to form irregularly, too thick at base and of varied color.  To remedy this it was suggested to have within and concentric with the basket a charger with flaring sides, into which the mixture was to be put.  When this charger reached a certain rotary velocity, the magma would be hurled out over the edge by centrifugal force and evenly distributed on the wall of the main basket.

SPINDLE.—­The spindle as now made is solid cast steel, and the considerations governing its size, form, material, etc., are identical with those for any spindle.  In order that the basket might be replaced by another after draining, the shaft has been made telescopic, but at the expense of stability and rigidity.  In Fig. 16 is shown a device to avoid crystallizations, which are apt to occur in large forgings, and would prove fatal should they creep into the upper part of the spindle proper in a hanging machine.  It consists of the secondary spindle, c.

DISCHARGING.—­The drained sugar may either be lifted over the top of the basket (in machines which stop to be emptied), or be cast through openings in the bottom provided with valves.  A section of the best form of valve may be seen in Figs. 15 and 17.  Fig. 23 is a plan of the openings.  The valve turns on the basket bearing.  It may be constructed to open in the same direction in which the basket turns; so that when the brake is put on, the inertia of the valve operates to open it and while running to keep it closed.  There are many other styles, but no other need be mentioned.

[Illustration:  Fig. 23.]

CASING.—­The different styles of casing may be seen by reference to the various drawings.  In one machine (not described) the casing is rigidly fixed to the basket, space enough being left between the bottom of the basket and the bottom of the casing to hold all the molasses from a charge.  This arrangement merely adds to the bulk of the revolving parts, and no real advantage is gained.

BEARINGS.—­The various styles of bearings can be seen by reference to the figures.  One which deserves special attention is shown in Fig. 16 and Fig. 19.  In one case it consists of loose disks, in the other of loose washers, rotating on one another.  They are alternately of steel and hard bronze (copper and tin).

“There is probably no machine so little understood or so imperfectly constructed by the common manufacturer of sugar supplies as the high speed separator or centrifugal.”  Unless the product of experience and good workmanship, it is a dangerous thing at high velocities.  Besides, its usual fate is to have an incompetent workman assigned to it, who does not use judgment in charging and running.  So that designers and manufacturers have been forced not only to take into account the disturbing forces inherent in revolving bodies, but also to make allowance for poor management in running and neglect in cleaning.