At a rather later date it may be well worth while to consider whether experience has not demonstrated the possibility of combining with a full subsidy scheme a modified scheme insisting only on vehicles of the right load capacity, and the adoption of all details of the standard control. In this way, if the true subsidy model continues to be somewhat unpopular amongst commercial users, a very fairly adequate reserve will be brought into being without any considerable trouble.
Turning now to the second of the two main points which the War Department have attempted to cover, we find the fulfilment of the scheme beset with much greater difficulties. Every attempt to secure standardisation in the parts of vehicles of different makes must necessarily entail expenditure by the manufacturers, both in getting out new designs and also in arranging for economical workshop processes. Such expenditure is only justified commercially if the sale of the resulting products is sufficient to secure profitable trading. Some allowance, of course, must be made for the added prestige accruing to a firm licensed to build for the War Office, but this is in itself insufficient encouragement. Consequently, every stipulation made with a view to standardisation must be covered by subsidy grants, sufficient to cover both manufacturer and user in respect of any additional cost or disadvantages in operation. The War Department has recognised the impossibility of asking for complete standardisation, and so killing the individuality of different types of vehicle. The tendency of any such process would be to throttle normal competition, and to prevent progress. Consequently, standardisation can only be attempted in certain respects where it appears for one reason or another to be highly desirable. For example, radiators are notably liable to damage, and consequently the connections of the radiator to the machine are standardised to allow of ready replacement of this essential as a whole. The radiators are mounted on trunnions, the bearings of which are in halves, and the positions and dimensions of inlet and outlet connections are definitely fixed. As an additional safeguard, a stout cord in the form of a bar or tube has to be placed across the front of the radiator. The engines are not standardised except in certain details, as, for example, the method of fastening on and driving the magnetos, which are arranged with a view to rapid removal and replacement whole. No high degree of standardisation is possible without incurring great expense and other disadvantages so far as concerns the design of the clutch and the change-speed gear, though the ratios of the latter are determined for reasons which will be explained later.