Note:  Do not rely on this information. It is very old.


Drum (cylinder), in machinery, is a hollow cylinder, round which ropes or chains may be wound for convenience of storage. The term is also used to denote wide pulleys fixed on shafting, from which belting passes to different machines. The drumarmature [Armature] is an arrangement in which coils of wire are wound lengthwise round a cylindrical drum in such a way as to enclose it completely. The wire is in several sections, the two ends of each section being carefully separated so that any electric current that is- induced in the wire by rotation of the armature in a magnetic field may be withdrawn and utilised. [Dynamo-Electric Machinery.]