representative sample. The study also included detailed costing of the traffic, and this not only confirmed the previous global estimates of the deficit but also gave quantitative indications of how large savings could be made by different methods of handling.
By the time of the test, the bulk of the traffic had been concentrated upon 550 stations throughout the country, but a further 400 stations still dealt with some of it. As with other traffics, the disparity in the loading of stations handling this traffic is very pronounced, as shown by Table 27, Appendix 1.
Before considering some other features of this traffic, it is worth devoting a little attention to the way in which, with a given total volume, the problem is intensified by handling it through a large number of terminals. For purposes of illustration it is convenient to consider, say, 1,000 terminals with equal throughput and each equally likely to send traffic to any of the others. Then, if the total traffic is 10,000 tons/day, each terminal will receive 10 tons and each will transmit 0·01 tons to every other terminal. If, on the other hand, the same total tonnage were to be concentrated upon 100 rail heads, each would receive 100 tons, and would transmit 1 ton to each of the others, so that daily consignments between terminals would be 100 times as great.
Although, in practice, terminals are far from equal in size, multiplicity of terminals tends to have this same effect. This is important with wagon-load freight, because it reduces the proportion of the traffic which can be handled by through trains. In just the same way, with sundries traffic it reduces the proportion which can be handled by the through loading of full vans.
Even at the best, sundries are a poor loading form of traffic, but the subdivision of flows by the multiplicity of terminals makes it necessary to dispatch vans part filled, to and from many of the lesser used terminals, or to combine loads to different destinations in one van for part of their journey and then tranship them at points along their route. This transhipment involves expensive handling.
At present, with the existing number of terminals, both these expedients are found necessary. As a consequence, the average wagon load is only 0·92 tons, and, in spite of the fact that there is a proportion of through van movement, consignments are, on average, transhipped more than once per journey.
As a result of the study, it is now proposed to reduce the number of main depots progressively to about 100, to limit light van loading and transhipment by reducing the frequency of forwarding to and from smaller stations in the meanwhile, and to concentrate transhipments on a few strategically placed points. At the same time, charges scales are being adjusted to bring them more into line with costs, and the present expensive documentation procedure is being simplified.
The volume and geographical distribution of present flows are shown by Map No. 7.
Full implementation of the plan, as it stands at present, would lead to a distribution of depots as shown by Map No. 8. It would involve the provision or re-equipment of a number of depots, at an estimated capital cost of £11 m., and, taken together, all the changes proposed under the plan would be expected to reduce costs by £20 m., at the present level of traffic.
While this would be a great improvement on the present deficit of £14 m., it does not make the traffic particularly attractive. Therefore, the plan will be
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