100 Streamliners "ON THE DOUBLE", says the public information flyer distributed in 1949 when the TTC received 100 multiple-unit PCC cars from Canadian Car & Foundry. The volume of streetcar and other traffic on the cross-town Bloor-Danforth route had reached its maximum during rush hours. To add more single streetcars in rush hours would not improve service, but only add to the congestion.

It was learned by experience, in Boston, Los Angeles and Cleveland, that two streetcars coupled could operate across an intersection as quickly as a single car, thus doubling the number of passengers carried across the intersection in one movement.

Covers were placed over the MU couplers when not in use. Note view of 4459, at the top of this page, taken on May 20, 1981 on Roncesvalles just north of Queen. These special automatic couplers carry 23 separate electric circuits that give the operator of the first car control of the motors, brakes and other equipment on both cars. Each car had an operator on board.

The Queen Street line also saw MU operation in rush hours for a time. However, this practice ended on the Queen line following the afternoon rush hour on Friday February 4, 1977.