Report on the Trials of Implements at Wolverhampton. 515 
which a thread is formed; and by means of another bevel- wheel, shaft, and 
liand-wlicel, N (Fig. 21), the windlass-man screws the spindle L one way or 
the otlior, tiio leverage bcinf; such that a very slight pressure upon the hand- 
wheel will thrust the blocks out with sufficient force to hold a drum without 
slipping against any strain, though the action may be so adjusted that the 
blocks shall slip in case of the implement encountering a root, a rock, or other 
immovable obstacle. While tlic windlass is in motion tlie hand-wheel slowly 
revolves, and upon the windlass-man catching hold of the handle tlic hauling- 
drum is instantly stopped ; both drums are tlien out of gear till a further 
movement of th.e hand-wheel brings into gear the drum wliicli had beeu 
l)aying out the slack rope. The spur-wheel is never stopped, so that all delays 
in pulling up and starting the engine are avoided ; and the stopping and 
reversal of the action of the drum are accomplished with the smallest possible 
motion, free from the slightest shock or jar. The "automatic friction-brake" 
upon each drum consists of an ordinary wood-lined brake-strap, BB (Fig. 22), 
embracing the outer surface of the rim or flange immediately over the driving 
toggle-blocks. The iron strap is attached to a differential lever, C, of the same 
character as that invented by the late Mr. Appold some twenty years ago, 
and used ever since w^aii the Society's friction-brakes. "When the rope is 
being jjaid out and the drum revolving in the direction of the arrow, the 
brake, so to speak, keeps itself tight, the strap with its wood blocks closing 
round the drum flange with a force proportioned to the difl'crence in length 
between what may be called the two arms of the lever C, or, in other words, 
the two distances of the points of attachment from tlie fulcrum D. On the 
contrary, when the drum is winding up the rope and revolving in the 
direction opposite to that of the arrow, the brake simply rests with its own 
weight ui)on the drum-flange, and by depressing the end of the lever, as 
shown by the dotted lines at E, opens itself so as no longer to compress the 
drum. Any requisite degree of tightness can be given to the brake by 
the adjusting screw F. A uniform strain is maintained upon the outgoing 
rope ; no slack can run off the windlass unless the lever be purposely lifted by 
hand ; and as the brakes pass into and out of action by the motion of the 
drums, no further attention is required after they have been once regulated, 
and there is no possibility of any entanglement from the attendant's carelessness. 
Messrs. Amies and Barford lay out their rope upon the roundabout system, 
but in place of the ordinary snatch-blocks and claw-anchors shifted by manual 
labour at the ends of the furrow, they employ two self-moving anchors, 
patented by Mr. S. Campain, of Deeping Fen, near Spalding, Lincolnshire. 
The very ingenious contrivance referred to consists of a strong horizontal 
Fig. 23. — Sketch of Campain' s Patent Self-moving Anchor, No. 2675. 
frame, mounted upon four ordinaiy anchor-discs and rollers (BB and C, 
Fig. 23), with a rope pulley, A, placed towards the forward end. The hind 
