ut forty-two inches in diameter and
eighteen inches wide, thus possessing a surface area of 2,376 square
inches, containing from 12,000 to 14,000 fine strong iron spikes. The
speed of the swift may be from 600 to 800 revolutions per minute. The
rags are fed by placing them on the traveling feed apron, and are thus
conveyed to the fluted rollers. As they emerge from the rollers they
are presented to the swift, and by strong iron teeth, moving with
exceedingly high surface velocity, they are torn thread from thread
and fiber from fiber. The fluted rollers run very slowly, and the rags
are held while the swift carries out this operation. By means of the
strong current of air created by the high speed of the swift, the
mungo is expelled from the machine through the funnel into a specially
arranged receptacle. If by any chance the machine should be
overcharged, that is, if too many rags are passing through the
rollers, the top fluted roller is raised up, and the rags are simply
carried, or thrown by the swift, over into a box on the opposite side
of the machine without being subjected to the tearing process. The top
roller is weighted by levers with weights attached to keep it in
position, thus bringing downward pressure to bear upon it, as it is
driven simply by friction. By the adjustment of the feed rollers in
relation to the swift, the length of the fiber may be varied to a
small degree.

=Extract Wool.= This is obtained from union cloths, that is, from
cloths having a wool weft and warp of cotton, etc., also from cloths
having the same material for warp, but possessing a woolen or mungo
warp or filling, etc. It is the wool fiber that is required. Therefore
the vegetable matter (cotton) must be extracted from it by the process
of carbonizing. To effect this, the tissue or rags are steeped in a
solution of sulphuric acid and water and then subjected to heat in an
enclosed room. The water is evaporated, leaving the acid in a
concentrated form, which acts upon the cotton, converting it into
powder. The powder readily becomes separated, and thus the cotton is
eliminated. The material that is left is well washed to remove all
acid, dried, and then passed through a miniature carder, to impart to
it the appearance of a woolly and a softer fabric.

=Flocks.= These are of three kinds, and are waste products of the
milling, cropping, and raising operations. The most valuable are those
derived from the fulling mill, being clean a