[Illustration]
In this case a cork with two balance-weights attached, in the shape of
forks as previously employed, is provided in addition with a pair of
legs, formed by the insertion of a couple of stout pins or small
round-headed nails into the bottom of the cork, as in Fig. 7. The figure
is placed upon an inclined narrow slip of wood at the highest point of
the incline and set gently oscillating, so that the weight is thrown
alternately on one side and then on the other, which will cause the
figure to make the descent of the incline in a series of jerks.