[1908]. Annular cylinder paddle engines.
[1909]. Overhead cylinder side-lever paddle engines.
In addition to the above some special types are occasionally employed, as the Willan’s three-cylinder plan for screw engines. See [No. 592], also varieties of [No. 593], high-speed types.
Section 104.—STRIKING AND HAMMERING: IMPACT.
The ordinary appliances for these purposes comprise hammers of all kinds and anvils or blocks of all shapes to suit the work, rammers and mallets of wood. The steam hammer being the machine almost invariably used, is too well known to need illustration. It is made with single or double standards, and though differing somewhat in details is practically the same machine wherever manufactured.
The following are apparatus employed for particular cases, and not so well known.
[1910]. The drop hammer, for power. The grip pulleys are put in gear by the hand lever to raise the hammer and shaft: it is sometimes worked by hand by a simple cord and pulley.
[1911]. Dead blow power hammer. The crescent-shaped crosshead bar has a positive motion from the crank pin, but the hammer head is attached to it by strong horizontal springs, and therefore has some little play above and below a horizontal line.
[1912]. The pile engine and monkey. The latter is generally raised by a hand or power winch, but a multiplying gear steam or hydraulic cylinder has been employed.