The increasing demand for more silent motor cycles has had its effect on inventors, and the Auto-Cycle Union is now engaged in carrying out tests on no less than four different types of silencer for attachment to existing exhaust systems. Further, in order to encourage manufacturers to aim at producing machines which will satisfy all the police requirements in regard to silence, and to convince the general public that a motor cycle need not of necessity be noisy, the Union is considering organising a Silencer Trial. We hope that the A.C.U. will not find this task impracticable, as it did when a Silencer Trial was proposed some time ago ; although we are quite aware that the proposition bristles with difficulties. The Union states that the regulations for the Trial have not yet been drafted, but it is hoped that the event will be carried out well before the Motor Cycle Show in November, to provide the buying public with reliable data on this important question.