Report from the Select Committee on Steam Carriages/Gibbs2
Mr. Joseph Gibbs, again called in; and Examined.
Have you any observations to make, in addition your Evidence given last Wednesday?—With a view of giving my opinion upon the best method of collecting tolls from Steam Carriages, I will commence by stating, that Steam Carriages can be constructed upon three several principles; my object being to show this Honourable Committee the difficulty in collecting tolls from Steam Carriages, except by the number of wheels without stopping the progress of that improvement in which they stand so much in need. Steam Carriages can be constructed as follows: first, Steam Carriages which propel themselves, and carry the supply of water and fuel, likewise passengers and goods; second, Steam Carriages which propel themselves, and carry the supply of water and fuel, but draw the load after them in a separate Carriage or Carriages; third, Steam Carriages which propel themselves and partly carry passengers, goods, fuel and water, and draw the rest in a separate Carriage or Carriages after them. This will show the great difficulty of levying a toll upon the weight of Steam Carriages; as for instance, 600lbs, of water and 100 lbs, of coke are requisite per hour on an even road, with a Steam Carriage as now constructed; but upon a road, abounding with hills, 1,000lbs, of water and 160 lbs, of coke will be required. Now if the weight is taken when the water and fuel are one-half diminished, say on the average 400lbs, of water and 65lbs, of coke, and the toll is levied upon the weight of the Steam Carriage, the Carriages (being drawn) paying as ordinary Carriages, the weight of water and coke can be transmitted to those Carriages which paying, not by weight but by the number of wheels, will of course receive an augmentation of from five to six hundred pounds additional weight. Likewise the danger from explosion will be increased if tolls are collected upon the weight of Steam Carriages, inasmuch as by loading the safety valve to double the pressure, a Carriage can be made to draw double the weight with only an alteration in the fire place, and an increase of water, air, and fuel; a diminution of weight will likewise take place to a considerable amount in the boilers and engines, although it is more essential an increase of strength should take place rather than any diminution. I can state a case in point; I have a Steam Carriage now constructed, from which I could abstract 900lbs, of iron without making it too weak to travel even on rough roads, but I should not be induced to do so except as a matter of economy in case the tolls are levied upon the weight and at too high a rate. The Steam Carriage as used upon common roads, being an invention of recent date, sufficient has not been done with them for practical men to decide what arrangements of machinery are best for their construction. It may be found hereafter that it is proper to place the Engine in one Carriage and the boiler on another, and blowing apparatus in another, all carrying other weights, so that three distinct Carriages (although they each carry only a part of a Steam Engine with them), yet if so arranged and tolls are collected by the weight of the Steam Engine, the whole of these Carriages would be liable to pay toll by weight. I think that in carrying heavy 19 de goods it is more than probable the Steam Engine will be on a separate Carriage, and the power transmitted to the hind axle of the Carriage containing the goods, by means of a flexible bolt or intermediate wheels, in order to obtain a slow motion of the Carriage, the speed of the Engines being the same; but does not this connect them, so that they may be considered as one Carriage, and liable to pay by weight? As it is probable that Steam Carriages or locomotive Engines will be used for ploughing, or to draw the plough to it, the Engine remaining during that time in its location, and only moving when the plough has completed its furrow, yet, in going and returning to the field, it may travel upon a turnpike road, and be subject to the toll of a Steam Carriage; an Engine of this description will be very heavy, and unless a provision is made, the farmer would be obliged to attach horses to it to prevent its being considered a locomotive Engine. It appears to me that the only method of collecting tolls is by payment (under proper regulation) on the number of wheels employed, and not on the weight of any part of the train, for if one part pays by weight and the other upon the number of wheels, the weight can be removed to a dangerous extent from the part paying by weight, and placed to an injurious extent upon the part by the number of wheels. I can well appreciate the difficulty the Committee must have to contend with in coming to a just decision as to the best method of levying tolls. I have been a number of years constantly having new inventions under my consideration, as well as being the inventor of several patent inventions which are now in full operation; therefore, without presumption. I feel myself qualified to give an opinion. I have constantly observed that all new invented machines entirely change shape, dimensions, weight and general arrangement of parts as they proximate to perfection, so that the perfect machine could not be recognized by persons unacquainted with the subject as being intended for the same purpose as the original machines, yet, during all these successive alterations, the principle of the machinery remained unchanged. I make these observations to show the difficulty of anticipating the ultimate power and dimensions of locomotive Carriages.
Will you exemplify your proposition as to the payment of tolls, giving 2s. as the amount of the tolls for a Carriage drawn by horses: what amount of tolls should be charged on the two following Steam Carriages, the one Carriage to carry passengers on itself, and to weigh four tons; and supposing in the second, the engine part of the Carriage to be separate, the Engine Carriage and the Carriage drawn weighing together four tons, should a higher amount of toll be chargeable on the one Steam Carriage than the other?—I think not.
Yet the one has four wheels and the other has eight wheels?—My opinion is, that it ought to pay the same tolls it does now, supposing they are of equal weight, the diminution of the horses being taken into account.
Then your proposition would be resolvable into charging tolls by weight?—Of course; I contemplate that a regulation will take place, that only a certain weight shall be placed upon the wheels, and the width of the wheels will come under a regulation.
Then it becomes absolutely a toll on weight?—Not exactly so; I am only stating the limits I think they ought to carry.
In the case stated on the one Steam Carriage carrying the passengers with the Engine, and the second the Engine being placed in a separate Carriage from that containing the passengers, both Carriages being of equal weight, that of four tons; but in the one case there being eight wheels, and in the other only four, would you charge a different amount of toll on those two Carriages?—I would charge in proportion to the weight carried. In stating this I conceive that there should be a maximum weight which Steam Carriages ought not to exceed.
What should you suggest as the standard of weight?—I have not turned my attention to that part of the subject, but I will do so if it is wished.
Are you aware what the average weight carried in vans is?—I have made inquiry from van proprietors, and find that they frequently carry six tons, including the weight of the van, but the average weight is about four tons, and the width of their wheels is from 2⅛ inches to 2½ inches.
Do you anticipate that steam will be applied shortly for the purpose of conveying goods in vans?—I believe it will; I contemplate the putting some vans on the road to be worked by steam.
Will such Carriages be on four wheels or on any greater number?—I think it probable that they will be on a greater number than four wheels, from six to eight wheels.
What do you conceive to be the maximum weight that ought to be placed on a wheel of three inches width?—One ton and a half ought to be the utmost limit.