To meet this requirement, the additional motor transport columns must also be capable of being mobilised with similar rapidity, and we are forced back either on to the last resort of commandeering any vehicle that comes handy, or else on to the preparation of a scheme which will provide a substantial reserve of vehicles of approved make and type, able to be made available at any instant at a few hours’ notice. Such a scheme evidently involves the payment to the owners of these vehicles of some sum intended to make up to them such loss as may result from their liability to have their vehicles immediately commandeered. These payments, moreover, must provide that the War Department shall have the right of periodical inspection of the cars, so that they may be well informed as to their condition, and may have certain knowledge as to whether they are being properly driven and maintained in such a way as to make them useful units of a fleet on active service. A scheme of this sort is called a “subvention” or “subsidy” scheme, and it is very generally admitted that such a scheme forms an essential part of the organisation of transport and supply in every country in which the civilian use of heavy motor vehicles is sufficiently extensive to make the principle of subsidy applicable on a working scale. Clearly, the amount of the subsidy which is offered to owners of motor vehicles of a suitable type must depend, in the first instance, on the conditions accompanying the payments. If--as to some extent in the case of Great Britain--the subsidy scheme applies only to vehicles of types which would not be employed for trade purposes were definite encouragement not offered by the Government, the payments must be more than sufficient to balance any disadvantages resulting from the use of the subsidy type vehicle, as well as the inconvenience of undergoing inspections. Again, if the War Department makes various stipulations as to features to be embodied in the design of subsidy vehicles, it is more or less certain that these stipulations will entail manufacturing expenditure resulting in an increase in the sale price of the machines as compared with the price of ordinary models of similar carrying capacity. Thus, the subsidy must also be sufficient to cover any increase in first cost to the user. If this increase is, let us say, £50, and the inconveniences entailed by adopting the type result in a loss of efficiency estimated, let us say, at £30 a year, the subsidy, if it is to form any real inducement, must evidently amount to a payment on purchase of about £60 at the least, followed by a payment of, let us say, £40 a year for three or four years.