wool, the greasy matter is dissolved, and along with the solvent enters
a reservoir. The machine is now set in motion, and the bulk of the
solvent is drawn off. Cold water is then admitted, and the machine being
again caused to rotate, the whole of the bisulphide is expelled. It is
a curious fact that, although wool soaks remarkably easily with carbon
disulphide, and at once becomes wet, cold water expels and replaces
almost all that liquid. This operation takes about twenty minutes, and
at one operation about 11/2 cwt. of raw wool may be treated. The wool is
then washed in suitable washing machines of the ordinary type, but with
cold water, no soap or alkali being employed. The bisulphide of carbon,
mixed with water, flows into a reservoir, provided with diaphragms to
prevent splashing, and consequent loss by evaporation. From its gravity
it sinks, forming a layer below the water; it is then separated and
recovered by distillation, and may be used in subsequent operations.

The point in which this process differs from the old and unsuccessful
ones formerly tried, is in the expulsion of the carbon disulphide. It
was imagined that it was necessary to expel it by means of heat or
steam. Now, when wool moist with bisulphide is heated, it invariably
turns yellow. No heat must, therefore, be employed. As already remarked,
the solvent is expelled with cold water.

The residue, after distillation of the carbon disulphide, is a grayish
colored, very viscous oily matter, still retaining a little bisulphide,
as may be perceived from the smell. It has not the composition of
ordinary _suint_, inasmuch as it contains no carbonate of potash, and
indeed little mineral matter of any kind. A sample which I analyzed
lost in drying 36.2 per cent., the loss consisting of water and carbon
disulphide. It gave a residue on ignition amounting only to 1.6 per
cent. of the original fatty matter, or 2.5 per cent. of the dried fat.