the sheets are not required to be folded, the arm H is moved to its
highest position, and there fixed, without stopping the machine: it then
delivers the sheets to the roller L, and by means of a blast of air and
a flyer they are laid on a table provided for them.

The rise of British factory-life and great energy in manufacturing began
with the invention of the spinning-frame by Arkwright, the power-loom by
Cartwright, the spinning-jenny by Hargreaves, and the mule by
Crompton--all within a space of twenty years ending 1785. To these must
be added the steam-engine by Watt, which made it possible to drive the
machinery, and the gin by Eli Whitney, which made it possible to get
cotton to spin. Much as iron has loomed up lately, the working of the
various fibres--cotton, wool, flax, hemp and jute--constitutes the pet
industry of her people, and very elaborate and beautiful are the
machines at the Exposition, especially attractive and less commonly
known being those for working long or combing wool, flax, hemp and jute.
The United States is not doing as much as it ought in the working of
these fibres, and the money which is paid for the purchase of foreign
linens and fabrics made of other materials than cotton and wool might,
some economists think, be employed at home in making them. The day will
come probably, but does not seem to be hastening very fast, when we
shall conclude to make our own linens, as we have within a comparatively
few years past determined in regard to all the staple varieties of
carpets.

[Illustration: INGRAM'S ROTARY PERFECTING PRINTING-MACHINE.]

One of the most important machines in the Exposition, from the American
point of view, is the "double Macarthy roller-gin," exhibited by Platt
Brothers & Co. of Oldham, England. It is a curious instance of how
machines sometimes revert to their original types. The oldest machine
for ginning cotton is undoubtedly the roller-gin, and it was known in
India, China and Malaysia long before Vasco da Gama turned the Cape of
Good Hope and opened the trade of the East to the Portuguese and their
successors. The common roller-gin of Southern Asia was shown at the
Centennial from Hindostan, Java and China, and is exhibited here from
Java. It has a pair of rollers about the size of broomsticks, close
together and turning in different directions, which pinch and draw the
fibre through, while the seeds are prevented from passing by the
closeness of the rollers. Whitn