Page 115 - Mario Bigon "The Morrow Guide to Knots"

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SIMPLE AND
COMPLEX TACKLE

A single whip with one pulley
(' ) does not reduce the effort
required to lift a weigh\. A
runner (2) divides in half the
effort necessary to move a
weigh\. Tackle with a double
whip has the rope passing
through two blocks. one
standing and the other
moving (3.4). Rigged as
here, it also reduces the effort
to a half. This tackle is used
on the boom sheet carriages
of small sailing boats. by
builders for hoisting concrete
buckets or small loads, and to
secure loads on roof racks.
The arrangement illustrated
in figure 5 spreads the load
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