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(Enclosure 3.)

DESCRIPTION OF IMPROVED RAILROAD,

SUITABLE FOR THE COLONIES,

AND FOR

BRANCH LINES, OR FEEDERS TO MAIN TRUNK RAILROADS.

It being very desirable that a system of Railroad be introduced, suitable for the requirements of a moderate traffic conveyed at a low rate of speed, and which may be constructed at a low cost within the means of our colonies, and of rural districts in Europe, the following description of improved Railroad is submitted, as being found to fulfil the conditions desired, and which has received the approval of many eminent engineers and capitalists.

In Railroad construction the weight of the locomotive engine intended to be used, and the speed proposed to be maintained, governs the strength and cost of structure.

The engines in use upon most European and American Railroads weigh from twenty-six to thirty-six tons, exclusive of the weight of the tender; and the running speed ranges from twenty-five to fifty miles an hour, with gross loads of from eighty to three hundred tons.

These weights and speeds involve the adoption of a permanent way (rails, sleepers, &c.) of great weight and solidity; the rails weighing from 65lbs. to 100lbs. per yard, and necessitating the construction of bridges and substructure of a correspondingly massive and expensive character.

It needs no argument to prove that a Railroad so constructed, and suitable for carrying the enormous traffic existing between the large European and American cities, is more than is demanded by the requirements of an ordinary traffic and a thin population, such as is generally to be found in our colonies and in our agricultural districts at home.

It is found that for the conveyance of a traffic beyond the capacity of ordinary macadamised roads, at a speed not exceeding twenty miles an hour, a locomotive engine, weighing not more than eight tons, running upon light rails, is sufficient.

Engines of this kind have, of late years, been patented by various inventors, such as Bloydell, Bray, Taylor, and others, whose traction engines are constructed for running on ordinary macadamised roads, and have been adopted by several ship-builders and others, and by Government for use in the national dockyards, and for service in India.

A locomotive engine, somewhat similar in principle to these, weighing eight tons, on four coupled wheels, with a gauge of 3ft. to 3ft. 6in., and capable of passing round curves of four to five chains radius, will draw upon a level Railroad, a gross load of 160 tons, at a speed of fifteen to twenty miles an hour; a gross load of sixty-five tons up an incline of one foot in 100, and of 35 tons up an incline of one foot in forty; and of twenty tons up an incline of one foot in twenty.

The weight of engine being reduced to about one-fourth that of ordinary locomotives, the weight and strength of bridges and permanent way can be reduced proportionably, so that, instead of having a rail weighing 65lbs. to 100lbs. to the yard, one of 30lbs. to the lineal yard is ample.

The width between the rails (or gauge) being only 3ft. to 3ft. 6in., curves of four to five chains radius being admissible, and gradients so steep as one foot in twenty employed, the natural surface of the ground can be the more readily followed; and heavy earthworks and viaducts being avoided, the formation of the road-bed, bridging, and all the work underneath the ballast usually denominated “the substructure,” will be of an inexpensive character.

The road-bed, at formation level, need not be more than sixteen feet wide, including three feet on either side the ballasting for side drains.

For the light engines and trains used on these lines, the heaviest portions of which do not exceed 10cwt. per foot run, wire suspension bridges, at a very low cost, such as those used in America, will answer every purpose; these are very durable, and are made up to spans of one thousand feet or more.

The permanent way, occupying a width of only six feet, may be laid down along the sides of common roads, and the traffic worked by horses, where it is not sufficient to necessitate the use of locomotive engine power. The rail used is five inches in depth, and weighs 30lbs. per yard; it is fished at the joints, and secured between longitudinal timbers of hard wood which give great vertical and horizontal stiffness; it is trenailed down to cross sleepers placed at intervals of nine feet.

The locomotive engine, used as before described, is adapted for speeds of fifteen to twenty miles an hour, and carries fuel and water for that distance.

The engine, being about one-fourth the weight of ordinary locomotives, will not crush the rails, which are something over one-third the ordinary weight while the bearing surface of the timber sleepers upon the ballast is little less than the ordinary area.

The sleepers may be laid upon six inches in depth of ballast; and, by proper attention to the drainage, the permanent way can be kept in perfect order at a small expense, as compared with the cost of upkeep of that of an ordinary Railroad.

In economising traction it is important so to construct the vehicles that they may be convertible to various uses; as, for example, the conveyance of wool, cotton, passengers, &c.

It is also important that the weight of the vehicles should not exceed one-half the weight of the load.

The vehicles, on this system, weigh one ton and a quarter, and the load is two tons and a-half.

Moveable seats are provided, so that the wagon becomes an open carriage, capable also of being covered in, and, by a peculiar construction of springs, it will carry a few passengers as easily as a heavy load of goods, the power of the springs varying with the load, and easing the road from damage. The axle runs loose in their boxes, and the wheels of the carriages run independently upon their axles.

One carriage will carry forty passengers. If required, first-class bodies can be mounted on the same frames, with a three feet six inch gauge; the carriage bodies are seven feet wide.

The weight of ten miles of line, including one engine, twenty carriages, rails, sleepers, and fastenings, will not exceed 800 tons; equal to the transit, in one train of 800 passengers, or