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Williams, Archibald

"Things To Make"


For the expenditure of quite a small number of pence, one may construct a
machine which will show fairly accurately what is the value of one's grip
and the twisting, power of the arms; and, even if inaccurate, will serve
for competitive purposes. The apparatus is very simple in principle,
consisting of but five pieces of wood, an ordinary spring balance
registering up to 40 lbs., and a couple of handles. The total cost is but a
couple of shillings at the outside.
Fig. 162 is a plan of the machine as used for grip measuring. The base is a
piece of deal 1 inch thick, 2 feet long, and 5-1/2 inches wide. The lever,
L, is pivoted at P, attached to a spring balance at Q, and subjected to the
pull of the hand at a point, R.
The pressure exerted at R is to that registered at Q as the distance PQ is
to the distance PR. As the spring balance will not record beyond 40 lbs.,
the ratio of PQ to PR may conveniently be made 5 to 1, as this will allow
for the performances of quite a strong man; but even if the ratio be
lowered to 4 to 1, few readers will stretch the balance to its limit.


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