The conveyor under consideration consists of a number of miniature carriages, which are each fitted with two spindles and four wheels. The carriage resembles a small contractor's truck (see Figs. 182 and 183); it is pivoted above its centre of gravity, round which pivot it can be tilted. The trucks are coupled together by a central coupling bar, and these coupling bars allow not only of an upward and downward motion, but also of a side movement within certain limits.