Page 114 - Mario Bigon "The Morrow Guide to Knots"

tackle

Tackle is a device used for lifting or moving weights; in its
original form it was made up of a system of pulleys through
which the force necessary to lift a specific weight was
reduced. Tackle is used at sea for handling ropes or to reduce
the strain on the running rigging and is a basic feature of
sailing. To understand the importance of tackle, you need only
remember that in a Force 5 wind (35 kph/22 mph) the
pressure on the sails is 10 kg per sq m/2 Ib per sq ft.
There are various types of tackle: a runner reduces the
power required to lift a load by half, apart from friction; a gun
or a luff tackle reduces it to athird; and winding tackle reduces
it to a sixth. In general, it is not advisable to use a greater
number of whips than this. While the effort needed to move a
weight is reduced in proportion to the increasing complexity
of the tackle, the time it takes and the amount of rope required
increase.

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