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PUBLIC RECORD OFFICE

Reference :-

CO 885/26

PUBLIC RECORD OFFICE, LONDON

ALLY WITHOUT PERMISSION OF THE BE REPRODUCED PHOTOGRAPHIC-

COPYRIGHT PHOTOGRAPH—NOT TO

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The loco-tractor system is still in its infancy, but we consider that the evidence already accumulated in regard to it is sufficient to make it well worth while to test its advantages directly in the East and West African Dependencies. Such tests have been carried out to some extent with promising results, and are still being pursued, in Uganda; and the Gold Coast, in which the conditions for mechanical transport are understood to be specially unfavour- able, offers perhaps another field for experiment. A point which experience is required to determine is whether the narrow macadam tracks will wear well in use, or whether their upkeep will be costly.

As a reduction in capital cost for the transport of a given amount of traffic is one of the main advantages claimed for this system, it would be most applicable where the line is over easy country and where the cost of the bridging, tunnelling and earthwork required would not be relatively heavy.

Mechanical Road Transport.

In comparing the cost of transport by road with that of transport by any form of railway, a salient fact to be remembered, as already pointed out, is that while the capital cost of the vehicles and the running expenses (depreciation, fuel, driver, repairs, &c.), fall upon the owners (whether Government or private), the capital cost of construction and the expenses of maintenance of the road are borne entirely by the Government. Looking at the matter, however, from the point of view of the whole community, it seems clear that a fair comparison can only be made by taking the aggregate of capital charges and maintenance and running expenses for both vehicles and roads.

Where the privately-owned traffic is considerable, it may be possible for the Government to recover from the owners, by suitable forms of tax, a share of the maintenance expenses (if not of the capital charges also) un the roads. Among the forms of tax for this purpose may be mentioned tolls, petrol taxes, licences for vehicles, "betterment taxes" on properties adjoining the road, and so on; but the restrictive effect of such taxes must be borne in mind and their proper incidence is difficult to secure. As efficient transport also benefits the whole community, a more general form of taxation may also be employed.

In some districts in Africa the Government can arrange for unmetalled roads to be con- structed and maintained entirely by native chiefs with tribal labour without any direct cost to itself, and such roads may be capable of bearing motor traffic during the fair weather season; but we are here concerned only with metalled roads suitable at any rate for light motor traffic at all times of the year, which must be constructed and maintained by the Public Works Department.

Apart from the cost of bridging which will naturally vary in any given case according to the configuration of the country to be traversed, the cost of the construction of such roads varies very greatly in different localities, depending as it does largely on the accessibility of good road material and local rates of wages. Two extreme cases may be compared. In Uganda, where road metal is abundant and the country generally favourable to road construction, the Director of Public Works estimated the pre-war cost of constructing a road 24 ft. wide with a 9 in. foundation of laterite lumps and centre width of 10 ft. metalled with granite at only £200 per mile. On the Gold Coast, on the other hand, where road metal is scarce and the climate and other conditions unfavourable to road construction, the cost of constructing an ordinary gravelled road, frequently impassable in the wet seasons, and only 16 ft. wide, is estimated at as much as £500 per mile before the war and £800 at the present time.

The cost of maintaining the road surface is similarly governed by local conditious, as well as by the density and weight of the traffic and also by the wheel tyres employed; it has for instance been represented to us that in certain parts road surfaces are rapidly destroyed by narrow solid tyres on wheels bearing heavy loads. The width of the road is also a factor affecting the cost of maintenance. On a narrow road the traffic is forced to follow in the same tracks, so that deep ruts are quickly formed; on a wide one the wear and tear-is spread over a corre. spondingly large area and the surface consequently lasts much longer. Thus the pre-war cost of maintaining the 24 ft. Uganda road referred to above is estimated at only £25 to £30 per mile per annum, whereas the maintenance of the 16 ft. Gold Coast roads is estimated to cost £50 per mile per annum in the country, where the traffic is lighter, and £80 near towns, although no heavier traffic than light motor lorries carrying a load of 15 cwt, on pneumatic tyres normally passes over them. Since the war the cost of maintenance has increased in the Gold Coast by about 30 per cent,

In England the cost of constructing a good water-bound macadam road, though it fluctuates according to the district, is said to be about £6,000 a mile, and the annual cost of maintenance to average £260 a mile; obviously roads of this class are out of the question in Africa.

The main items in the running expenses of a motor lorry are the wages of the driver and the cost of fuel. The cost of employing European drivers in Africa would generally be pro- hibitive, while on the other hand, the native driver cannot, as a rule, be trusted to do more than the simplest running repairs, and requires careful supervision. For these reasons the vehicle must return to the depot each evening, and the range of its journey is limited to about 25 miles out and 25 miles back, or a round journey of 50 miles,

The fuel commonly used hitherto in Africa for road lorries is petrol, the price of which is at present high everywhere, and in West and East Africa is so onerous as to be almost prohibitive. A liquid substitute for petrol, termed "Natalite," consisting of alcohol mixed with a proportion of ether and denatured with trimethylamine, is manufactured in Natal and has been in use for several years in South Africa; and it is understood that it is about to he manufactured also in Mauritius and possibly in Kenya. The question of producing alcohol for

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power purposes on a large scale within the Empire, which is being investigated by the Imperial Government and the trading interests concerned, has not at present reached a stage at which it can usefully be considered by this Sub-Committee. of reducing the fuel cost of road transport, which appears to be deserving of the immediate But another very promising method attention of the Colonies and Protectorates in East and West Africa and elsewhere, is the application of producer gas tó motor vehicle propulsion.

Producer gos is made by passing steam and air through a retort containing a bed of incandescent fuel such as anthracite, coke, or charcoal, or indeed any carbonaceous material, such as vegetable refuse. Charcoal, in particular, can be produced in many parts of West und East Africa in unlimited quantities at an almost negligible cost, and produces little or no tarry matter on combustion, and it is thus eminently suitable for experiment in those parts of the world.

The application of gas-producing apparatus to motor vehicles is still in the experimentál stage, but striking progress has recently been made. A lorry loaded with 3 tons of sand and fitted with an ordinary petrol engine driven a suction gas plant was recently run from London to Godalming and back without showing the least sign of any trouble, the course including the ascent of Guildford High Street (a gradient of 1 in 10). A description of two plants designed for motor vehicles which were recently exhibited before representatives of the Imperial Economic Transport Committee is attached,

The two chief drawbacks to the use of producer gas for propelling vehicles are (1) the time required to make the initial start, and (2) the reduced power obtainable (estimated at 30 per cent.) as compared with petrol when an engine designed for petrol is employed. The first of these could easily be mitigated, where a number of vehicles are employed, by charging the producer with hot fuel in the same way as railway locomotives are charged with hot fuel in the running shed. The second disadvantage could also be overcome by providing cylinders uf 30 per cent, greater capacity. With engines designed for using petrol the only means of compensating for this loss of power is to lower the gear; the tractive effort of the vehicle would then be maintained but the maximum speed proportionately reduced. This reduction of speed would, however, be no disadvantage in Colonial conditions.

The application of producer gas to a fleet of vehicles provided with petrol engines would mean 30 per cent. less mileage in a given time, and consequently, to maintain the same service, an increase of 30 per cent. in the number of vehicles might be required, involving a pro- portionate increase of all running costs, but the enormous economy in the cost of fuel would far outweigh this disadvantage. It has been estimated that with a fuel such as anthracite, taking its cost at £3 per ton, the fuel economy would be equivalent to using petrol at 3d. per gallon; and charcoal could no doubt be produced in West Africa for much less than £3 a ton, as the natives in every village manufacture it on a small scale for their own purposes.

Even at its present stage of development the use of producer gas for motor transport appears to have great possibilities, and with the improvements in design which are certain to be made as the result of further experience its ultimate success seems assured. It could also probably

be applied with advantage to the road-rail tractor described above.

Arrangements have been made both in Nigeria and Uganda to fit the apparatus to standard lorries for experimental purposes, and as the expense of doing this amounts only to about £100 for each lorry, it should be worth while to try the experiment in other Colonies also.

Mechanical Transport without Metalled Roads.

For the sake of completeness we refer briefly to the forms of mechanical transport--such as caterpillar traction-which do not require the construction of metalled roads. Sir Frederick Lugard, in his report on the amalgamation of Nigeria and its administration from 1912 to 1919, presented to Parliament in December, 1919 [Cmd. 468], recommends the ped-rail system, with tractor and trailers, as the best solution in his opinion of the mechanical transport problem for Nigeria generally. This opinion is not, however, founded on any actual experience in the country. Mr. Stafford, of Uganda, put before us an interesting suggestion of a utility" caterpillar tractor capable of being employed successively to plough cotton lands, as general a stationary engine to gin the seed cotton, and finally to transport the products to a railway or port. He anticipates that if a suitable machine for these combined purposes could be designed, working with producer gas, the cotton industry in tropical Africa would be revolu tionised. It is understood that a well-known engineering firm has undertaken to investigate the problem.

General Remarks.

Speaking generally, the chief object of a Colonial Government in determining whether new extensions of transport communications should take the form of standard gauge railways, narrow gauge railways, or roads, should be, as already indicated in this report, to secure the transportation of goods at the lowest cost per ton-mile.

Other considerations may, however, enter into the problem. One of these is the speed required. In the memorandum presented by the London Chamber of Commerce it is pointed out that the ordinary speed of West African passenger trains, even mail traina, is under an average of 20 miles an hour, while the ordinary goods train average is between 5 and 10 miles an hour; and the inference is drawn from this that railways of narrower gauge would be slower still, and may therefore be put out of court. But this by itself does not appear to us con- clusive. It is no doubt very desirable to have a reasonably fast passenger service on a long distance trunk line, but on comparatively short branch lines, and under ordinary West African conditions we imagine that speed would be quite a secondary consideration,