The fact that our Government has called for bids for supplying 10,000 motorcycles indicates that the value of these machines, as demonstrated in the operations in Europe, is appreciated; but, as half the number are to be supplied with sife-cars it is uncertain how it is expected to use them. Moreover, the number called for is decidedly small when we consider that the British have over 75,000 such machines in their army alone, without counting the swarms employed by the other Allies. A suggestion that motor cycles with side-cars are valuable for quickly bringing no bodies of armed men to critical points appears plausible at first, but there are no records in European experience that such procedure is practical (says the ‘‘Scientific American’). These vehicles must use the same roads as the motor transports, and it is obvious that when the fate of thou sands of men is depending on the prompt arrival of ammunition the supply train cannot be delayed by a small detachment of motor cycles. The ammunition train must have the absolute right of way. More over, as far as we have learned, the only side-car combination that is in use in the European armies is the one arranged for carrying machine guns, and these have proved of inestimable value, for in many cases a small machine gun motor cycle de tachment has been able, by the rapidity of its movement, to take and to hold im portant positions where it was impossible to bring up an effective body of riflemen in time. A great number of these mobile machine gun batteries are attached to every division, and have been found in dispensable. For the transportation of machine guns a powerful and rugged motor cycle is re quired, and for this use our American machines are without doubt the best in the world, for it has been fully demon strated that our motors are the equal in efficiency and power of any that have ever been produced, and the frames are superior in strength an id rigidity to any foreign built machines, a result of our long ex perience in building for the rough roads found in many parts of this country. An other strong point in American machines is the ample road clearance, which is very important on the rutted and shell-furrowed roads in regions where active fighting is going on. Besides their use in transporting machine guns the motor cycle has been found of great value for the carrying of despatches, and for this purpose solo machines are used exclusively abroad, and our informa tion regarding them is mostly derived from British sources. When the war started the English authorities turned to their own manufacturers, and to secure a suffi cient number of machines every kind avail able was taken. These included many small machines, running from 2$ to 5 horsepower, and doubts were freely ex pressed as to the utility of these low powers, for everyone imagined the de spatch rider as careering along, over shell pitted roads, and across rough fields, at racing speed. Experience, however, has changed all of these ideas, and it has been found that light machines of moderate power are best adapted to this important work. In the first place it is impossible to ride the rough roads at high speed, and the best results are had by steady plugging at moderate speeds, and great power is therefore not necessary. More over light weight was found absolutely necessary because on the overcrowded roads at the front the motor cyclist had to get out of the way of the transport trucks, or get run over, and to do this he had to take to the ditch, dragging his machine clear of the road. This and lifting it out of shell holes, up banks and over obstructions, requires some strength, and few men could survive a day of this kind of work handling a heavy, high-powered machine. The best motorcycle for de spatch carrying is undoubtedly a single cylinder machine of from three to four horse-power, for it has ample power for its special work, it can be reasonably light, and most important of all, it is simple, and that means much where the rider must usually improvise his own repairs. The smaller English machines used at first have undoubtedly been unsatisfactory, and there has been serious trouble from broken frames and forks, and in this respect our motor cycles are undoubtedly superior. An American despatch rider as he ap pears in manoeuvres, has for his mount a big machine weighing, with equipment and fittines, in the neighbourhood of 40Mb., apparently a prohibitive weight in actual service. He carries a regulation rifle in a boot strapped to the front forks. Experi ence abroad has shown that it is impracti cable and useless for a despatch rider to attempt to carry a rifle, and the only weapon carried in the European armies is a good automatic pistol. The daredevil despatch rider of the public prints, careering across country at racing speed, has disappeared, if he ever existed, and the present day courier is the steady-going, determined man who gets through in spite of every obstacle.