Page 535 - The Ashley Book of Knots

THE ASHLEY BOOK OF KNOTS

direction that a rope is coiled (clockwise). The blocks are placed

together on a dean deck and the bottom shivs are rove first. Appar-

loa ently the point is not considered important as, even on well-found

ships, tackles are rove in both ways.

Running rigging may be rove off by marrying the end of the new

rope to the old fall and hauling the new one through. Power is in-

creased by adding to the number of $hivs around which a rope

(called the fall) passes.

3208. A single whip is called a tackle, although it does not increase

the power.

On the accompanying diagrams, the figure placed on the weight

31 '3111

1 represents the increase of power at that point. no allowance being
3 made for loss by friction or otherwise. The figure 1 on the weight

means that the pull and the lift are equal.

3209. A runner is the same as a single whip, reversed. The figure

12.12. 11 2 means that the lift is double the effort spent.

3210. A single purchase. A purchase is a tackle that has the same

number of shivs in both blocks. With the fall leading to the upper

block of a purchase, the increase in power is always represented by

an even number.

3211. A gun tackle.

3212. A luff tackle.

3213. Luff tackle inverted.

3214. Double purchase (mechanically the same as long tackle

~3232).

3215. Double tackle.

3216 18 3216. Winding tackle. This is about the largest tackle commonly

found on sailing ships. It is used as a fish tackle (at the anchor) and

also as a cargo tackle. Lever (1808) gives it for a jear tackle and

Anden;on (1625) gives the same thing for j ears, except that the

standing part is bent to the yard instead of to the fall block, the

principle being the same. As each shiv added increases the time re-

quired to lift a load, blocks larger than are needed should be avoided.

On blocks with over two shivs, the standing part should lead to the

cheek of the block and not to the breech, as shown in ~ 3 170.

~111 ~ 2.1 ')

3217. Winding tackle reversed.

6 6 7 3218. Threefold or triple purchase.

3219. Threefold or triple tackle.

3220. Four-by-three tackle.

)2.l0 'l'212

•
3221. Three-by-four tackle.

3222. Fourfold purchase.

3223. Fourfold or quadruple tackle.

Purchases of five and six shivs with steel wire rope are used for

steamship cargo tackles. Ball or roller bearings are employed.

~1l1

8 8

( 52 6 ]