414 
PORTABLE SHEERS. 
Front guy holdfasts .—Two anchors, chained together and loaded, were 
used for the front guy holdfasts. 
The main tackles consisted each of a tackle of two 18-in. treble both- 
ways blocks, and 6J-in. rope. 
The running tackles for back guys are exactly a duplicate of the main 
tackles. 
Winches .—Four crab winches, strong pattern, are used—two to work 
the main tackles, and two for the runners of back guys. 
Slings are of 12-in. rope, intended to be used double, being 21 ft. long. 
There are two—one to be applied before, and the other behind the 
trunnions, and lashed together under the blocks of main tackles. 
Note.—N o driving apparatus was supplied to drive tlie “posts, picket,” 9ins. x 9ins. x 13ft. 
A monkey for this purpose would he necessary in soft ground. 
Detail op Operations op Raising the Sheers. 
1. The spars having heen landed close to the dock, they were 
placed on rollers and their butts loaded with “ pig-iron,” till the centre 
of gravity was brought far enough back to allow of their being 
launched across the dock till their head rested on rollers on the other 
side. 
2 . In this position the head gear of the spars was pinned, and two 
light uphers securely lashed, one near the butts, and the other about 
§ yds. up the spars. 
3. The Royal Engineers had meanwhile sunk a solid foundation of 
concrete for the shoes, on which in due course the butts of the spars 
were placed, resting on a cushion of soft wood and junk, to prevent 
the sharp edge of the bowl of the oak shoes cutting the foot ropes or 
injuring the spars. 
4. The foot rope consisted of a chain passed through two strong 
eye-bolts in the face of the dock, the ends brought up opposite the 
shoes. A heavy gyn tackle was then hooked to the chain, and the 
other block was lashed round the butt. The running ends of the 
tackles passed round the shoes, so that the tackle could be eased off by 
one man, or tightened up by one of the winches, if necessary, extra 
ropes being used as pr event or!. 
5. The centre line of the whole system was made to coincide with 
the line adopted on a previous occasion in erecting 45-ft. sheers, and 
the old holdfasts and old shoes werG utilised in re-erecfcing those sheers. 
This completed, the 45-ft. sheers stood between the legs of the 70-ft. 
sheers. 
6 . The main tackle falls of the 45-ft. sheers were now lashed to the 
large sheers at the upper upher or cross spar, and a barge lent by 
the navy was grounded at low water in the dock. 
7. The navy lent a quantity of old skidding, which was built up 
