We all know how useful it is to be able to calculate distances approximately when upon an excursion or walking tour, and much trouble is taken by many tourists to ascertain the number of miles they may have walked in a certain time. The rapid success which the Pedometer has gained is a testimony to the need it has adapted itself to fill.
The pedometer is much like an ordinary watch in appearance and size. We perceive a dial with figures and spaces to show the number of paces walked. The cut represents the mechanism, which is exceedingly simple.
Fig. 884.—Pedometer.
In the fig. 884, B is a counter-poise at the extremity of a lever, which oscillates around an axis, A. A screw, V, serves to limit the extent of these oscillations, and a spring which acts upon the counter-poise holds the latter to the upper end. The apparatus is completed by a movement which counts the number of oscillations of the lever.
So much being understood, it will be presumed that if we give to the instrument an “up-and-down” movement, the spring which holds the counter-poise, B, being too weak to compensate the force of inertion of the latter, it gives way and presses against the screw, V. When the opposite movement takes place the counter-poise is at the end of its course, and so on. Thus during a walk each step produces an oscillation which the counter registers.
In the hands of a careful observer, such a pedometer is capable of registering exact results, and the number of paces being counted, a very good idea of the number of yards and miles passed over can be arrived at.
