of raw cotton.  Payment is made in proportion to the work done, and in the less remote country districts is at the rate of about one penny for each pound carded.  As regards spinning and weaving, in the first of these branches of cotton manufacture the Japanese have largely had recourse to the aid of foreign machinery, but it is still to a much greater extent a domestic industry, or at best carried on like weaving in the establishments of cotton traders, in which a number of workers, varying from 20 to 100 or more, each with his own spinning wheel, are collected together.  Consul Longford says the spinning wheel used in Japan differs in no respect from that used in the country 300 years ago or (except that bamboo forms an integral part of the materials of which it is made) from that used in England prior to the invention of the jenny.  The cost of one of the wheels is about 9d., it will last for five or six years, and with it a woman of ordinary skill can spin about 1 lb. of yarn in a day of ten hours, earning thereby about 2d.  There are at present in various parts of Japan, in all, 21 spinning factories worked by foreign machinery.  Of four of these there is no information, but of the remainder, one has 120 spindles; eleven, 2,000 spindles; two, 3,000 spindles; two, 4,000 spindles; and one, 18,000 spindles.—­Journal Soc. of Arts.

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[Continued from SUPPLEMENT, No. 612, page 9774.]

CENTRIFUGAL EXTRACTORS.

By ROBERT F. GIBSON.

SUGAR MACHINES.—­Besides separating the crystalline sugar and the sirup, secondary objects are to wash the crystals and to pack them in cakes.  The cleansing fluid or “white liquor” is introduced at the center of the basket and is hurled against and passes through the sugar wall left from draining.  The basket may be divided into compartments and the liquor guided into each.  The compartments are removable boxes and are shaped to give bars or cakes or any form desired of sugar in mass.  These boxes being removable cannot fit tightly against the liquor guides, and the liquor is apt to escape.  This difficulty is overcome by giving the guides radial movement or by having rubber packing around the edges.

Sugar machines proper are of two kinds—­those which are loaded, drained and then unloaded and those which are continuous in their working.  The various figures preceding are of the first kind, and what has been said of vibrations applies directly to these.

The general advantages claimed for continuous working over intermittent are—­that saving is made of time and motive power incident to introducing charge and developing velocity, in retarding and stopping, and in discharging; that, as the power is brought into the machine continuously, no shifting of belts or ungearing is necessary; and that there are less of the dangers incident to variable motion, either in the machine itself or the belting or gearing.  The magma (the mixture of crystalline sugar and sirup) is fed in gradually, by which means it is more likely to assume a position of equilibrium in the basket.