A device carried on the person, for counting the number of paces walked, and hence determining the distance. Counting was usually carried out by a pawl engaging with a ratchet wheel, the pawl being operated by a lever or weighted sector which rose and fell with the rise and fall of the body in walking. Occasionally an adjustment for length of pace was provided, the ratchet wheel having fine teeth and the number of teeth passed over step by step being pre-set. Otherwise the pedometer was usually set to record one mile for 1,000 double paces. Pedometers were made in the form of watches in the late 18th century, in particular by Ralph Gout and Spencer & Perkins of London.