Part 11

Nor would the quantity of air that rushed by the _piston-end_ of the carriage be at all important, even when travelling at _very_ great velocities, and with heavy loads. In a tunnel of the diameter which would be proper for such lines as those to Bristol, or South Wales, the pressure requisite to move a load of 100 tons would not be more than about 100 grains per square inch; which would cause air to rush past the piston-end of the carriage at the rate of about 30 feet per second. Therefore, even could no better adjustment of the piston-end of the carriage and the inside of the tunnel be effected, than took place with respect to that at Brighton, only 90 cubic feet of air per second would rush past, even were the carriages standing still; which is only one-tenth of what the air-pumps I used there were capable of exhausting in the same time; while, on such a line as the Bristol, or South Wales, it would not be one-hundredth of what the exhausting apparatus would take out in the same period; so that not one-hundredth of the power would be lost by it: and even this hundredth could easily be reduced to a thousandth: the space left between the piston-end of the carriage in the tunnel at Brighton being _purposely_ an inch and a half in width, in order that I might shew, by actual proof, how utterly unimportant was _that_ objection which engineers of the highest name and reputation had assured me must, _inevitably_, prove fatal to the motion of _any_ carriage in _any_ tunnel.

And as the carriage, instead of standing still, would be moving forward, the loss of power, which would, otherwise, result from the pressure requisite to _give the velocity_ as well as move the load, would be equally unimportant as that arising from the pressure requisite to move the load alone.

With pressures so trivial as these capable of producing practical effects, and with it fully practicable so to adjust the “piston” part of the carriages to the tunnel, as to render this “windage,” or leak, perhaps less than one-hundredth of that which I _purposely_ caused in the tunnel at Brighton, there can be no difficulty, either in preventing any important quantity of air from rushing past the carriages; or in so connecting the “lengths” of which the tunnel would be composed, as to render the joints air-tight.

And as there are _no_ objections which the engineers can bring forward, that cannot be replied to in an equally satisfactory manner, I need not trouble you with any additional answer to them.

It is now four years ago since the locomotive engine competition took place on the Liverpool and Manchester Railway. In all probability no proprietor of the Kensington Canal happened to be present at that contest; yet is it equally probable that all were as fully convinced of the fact from the accounts which appeared in the newspapers, as if you had seen it. Now though I cannot give the conviction arising from the evidence of your senses, yet can I give stronger evidence than the public vehicles of intelligence gave as to that competition, by referring you to the public authorities and records of Brighton, to know whether I did not carry an appointed number of its inhabitants to and fro, as the locomotive engines went during that competition; “when,” says Mr. Treasurer Booth, in his “Account of the Liverpool and Manchester Railway,”—“the prescribed distance, it should be understood, was, owing to the circumstances of the railway, obliged to be accomplished, by moving backwards and forward on a level plane of one mile and three quarters in length.” I did not, it is true, carry those gentlemen so far as those engines went. Nor, indeed, was there any occasion for it. Had it been necessary, they could have continued riding to and fro in my tunnel, as long as the locomotives ran to and fro on the railway. But, as when they had satisfied themselves that there was no trickery in the motion of the carriage, and that it was _really_ moved by the air, they had, then, seen all that it was necessary to see, to convince them that a longer tunnel would enable me to move a carriage equally far, as a longer railway would have admitted of the locomotive engines going, they gave over riding, “because,” as the Editor of the Brighton Herald says, in the extract which I have quoted from that paper, “because they became so convinced that the invisible and intangible medium we breathe, might be rendered a safe and expeditious means of getting us from one place to another, as to be tired of riding.”

Were it necessary for your interest that a gas-pipe should be laid throughout the line you propose, your inquiry of the engineer you might employ would be, not whether the gas would pass through such a length of pipe, because you know that to have been long established, and to be every day acted upon, but what would be the _expense_ of it; that is, it would be a money question, not a question of practicability.

The tunnel I constructed at Brighton was nearly eight feet in diameter, while the air-pumps I adapted to it were large enough to make an artificial wind blow through it at the rate of ten miles an hour. And doubling, tripling, quadrupling, &c. &c. the size, or number of the pumps, would have doubled, tripled, &c. &c. the rate at which this wind blew.

A common size for gas mains is eight inches. Were it propounded to you—“Can a mouse run through a rat-hole, let that bole be as long as it may?” your answer would not be dubious. Why, then, if it be proved, that we can, with pneumatic apparatus of an almost infinitely less efficient nature than that which I purpose using, make air move through smaller pipes five, fifteen, or even fifty miles long, {72} should any doubt be entertained whether air-pumps will cause it to move through one of eight feet in diameter; more particularly, when it is well known, that the larger the pipe the less the proportionate friction; and when your line will be little more than two miles long.

The pressure by which the gas is driven through the pipes of the work I know the most of, is equal to an ounce and a half per square inch. A similar pressure on the carriage in my tunnel would have moved above one hundred tons. The length of your line would be only about eighty times longer than the tunnel I constructed; and as the area of your tunnel would be nearly 150 times larger than the eight-inch mains through which the gas is carried many times farther than the length of your line, there need be no more question as to whether, or not, the principle will act throughout your line, merely because it is eighty times longer than my tunnel, than there is whether gas would pass through eighty lengths of gas-pipe.

And as the joints which connect the different “lengths” of gas-pipes can easily be made air-tight, so could the “lengths” and joints of the tunnel. “Under the trivial degree of exhaustion which will be necessary,” says the Report of the Russian Engineer Officer, “rendering the tunnel sufficiently air-tight will be far less difficult than is at first supposed. Indeed, I see so many different ways of doing it,” continues the Report, “that I am satisfied it would not, in practice, prove more difficult than, nor, indeed, so difficult as, causing some canals I have seen, to retain the water let into them.” Following up the illustration which this gentleman thus gives, I beg to assure you I will guarantee that the tunnel shall not leak, or let air improperly in, so much as I see the basin of your canal leaks water out.

Adverse as were the original circumstances of the great father of canal navigation in England, yet did he put to signal shame the opposition and predictions of the engineers who proclaimed him a madman for pretending that it was possible to carry a canal over a navigable river. Ten thousand times more mad as the engineers of the present day proclaim me, and a hundred thousand times more absurd and “impossible” as they have pronounced my proposition to be, yet, owing to having in my favour (what Brindsley had not in his) the circumstance of my principle having been tried, I am enabled to oppose to their ridicule and sneers the FACT that I have proved it on a scale, which, as relates to size, was fully, and in _every_ particular practical; while it was less than practical in point of length, only because no individual could do that which it requires a public company and an act of parliament to do, that is, lay it down between places for actual trade.

Short, however, as it was, yet was it many times longer than the pipes through which gas was first carried, to prove the practicability of lighting our streets with that illuminator: while its length was great enough to be equally conclusive, as the movement of the first steam-vessel built by the introducer of steam-navigation.

“When,” says Fulton, “I was building my first steam-boat at New York, the project was viewed by the public either with indifference or with contempt, as a visionary scheme. My friends, indeed, were civil, but they were shy. They listened with patience to my explanations; but with a settled cast of incredulity on their countenances. I felt the full force of the lamentation of the poet:

‘Truths would you teach, to save a sinking land, All fear, none aid you, and few understand.’

“At length the day arrived when the experiment was to be put into operation. To me it was a most trying and interesting occasion. I invited many friends to go on board, to witness the first successful trip. Many of them did me the favour to attend as a matter of personal respect; but it was manifest that they did it with reluctance, fearing to be the partners of my mortification, and not of my triumph.

“The moment arrived in which the word was to be given for the vessel to move. My friends were in groups on the deck. There was anxiety, mixed with fear, among them. They were silent, and sad, and weary. I read in their looks nothing but disaster; and almost repented of my efforts. The signal was given; and the boat moved on a short distance, and then stopped—and became immoveable.”

When _my_ opponents can prove, that because Fulton’s first steam-vessel would, on its first trial, move only the “short distance” stated in the above quotation, it was, therefore, impossible to move any other vessel farther by means of steam, I may heed the clamour they raise about my proposition not being practicable through a long line of tunnel.

Until then, I can consider it only as a proof of their knowledge being on a par with the wisdom of that most learned opponent of Galileo’s theory that day and night are occasioned by the revolution of our planet on its axis, who, in answer to the query, “How then is it that the sun gets back to, and always rises in the east of a morning?” replied, that he went back by night, when nobody could see him.

In concluding, I will endeavour to guard against a circumstance that may otherwise be injurious to me, by an observation. You will perceive that the evidences which I have quoted have been in existence six or seven years. How then, it may be inquired, is it, that a method which is spoken of so highly as those evidences speak of this mode of conveyance, should have remained seven years without having been put into actual practice, or brought any nearer to that consummation than it was when those documents were written?

During the many years which elapsed between the period of Columbus’s first proposing to Ferdinand and Isabella the discovery of America, and their actually setting him afloat to do it, he sent his brother Bartholomew to England, to lay the proposition before our Seventh Henry, who, he expected, would entertain it. Henry did entertain it; and would have possessed England of the southern more firmly than she afterwards became possessed of the northern half of America, but for the misfortune which prevented Bartholomew Columbus from approaching him, till Isabella had agreed with, and dispatched Columbus himself.

“In his voyage to England,” says the historian of America, “Bartholomew Columbus had been so unfortunate as to fall into the hands of pirates; who, having stripped him of every thing, detained him a prisoner for several years:” reducing him to such poverty, that when released from captivity, he could in no other way obtain the means of procuring a dress fit for his appearance before the king, than by employing himself in drawing maps.

Circumstances which, morally speaking, are _exactly_ similar to this captivity and imprisonment of Bartholomew Columbus—excepting that they failed in compelling me to sign away the patent rights, to wrest which from me they were instituted—have equally hindered and reduced me: occasioning the destruction of the tunnel which I constructed to demonstrate, practically, the truth of the proposition; and depriving me of all means of proving it, except by carrying small things on an experimental scale, instead of persons on a practical one.

As relates to myself, I have no desire to obtrude the details of the oppression and injustice practised upon me, on any one.

But with respect to the subject I advocate, I am most anxious that the whole world should know that I court the _fullest_ inquiry, and am ready to answer _every_ question.

As one proof of this, and to shew that there is nothing which I need to blush for, any more than Bartholomew Columbus had cause to blush for being imprisoned by the pirates, I beg to direct your attention to the annexed copy of the Petition I presented to Parliament; of which only an extract is given in page 19. Soliciting the favour of your perusing it, I have the honour to be,

My Lords, and Gentlemen,

Your very obedient,

And most humble Servant, JOHN VALLANCE.

APPENDIX.

AS the first evidence that “the observations which will be found in the course of this letter relative to the effects of momentum, are not of such recent origin in my mind, as Mr. Badnall states his idea relative to the undulatory railway to have been in his,” I observe, that in the specification of my patent, after declining to level for the course of my tunnel by cutting through hills or filling up vallies, as is done for railways, I state, that I carry it up and down them (provided they are not precipitously abrupt) for the reason, that “the momentum it (the carriage) may thus acquire, will be advantageous in other ways than merely carrying itself forward.”

Secondly. The last sentence of the paragraph commencing “Tenthly,” in the Report of the Russian Engineer Officer, implies that that gentleman had understood what I have stated relative to this effect of momentum, from my communications to him.

Thirdly. The plan and section of the Brighton and Shoreham Pneumatic Railway, which I deposited in the County Court in 1827, and in Parliament at the beginning of the session of 1828, prove that the whole rise from Shoreham Harbour to the spot on the _top_ of the hill _above_ Brighton (old) Church, where I intended said Pneumatic Railway should terminate, was (I forget the exact amount, but) about 180 feet: of which rise, about 150 feet took place in the last half mile; giving a rate of about 1 in 18: up which rise I looked to momentum, as the _principal_ means of getting the 100,000 tons of goods I calculated on carrying between those places.

Fourthly. In my letter to Mr. Ricardo, in answer to his pamphlet against me, I observe, that after totally omitting to take into consideration the important effect which momentum (_as well of the air itself as of the vehicle_) would have in modifying the motion, and preventing the stoppage of the carriage, in the way you describe at page 21, you exclaim, “This then, is a true philosophical explanation, of what will take place in the action of a carriage impelled by atmospheric pressure!”

Against such philosophy as this I protest, in justice both to myself and the public. As the basis of lectures delivered at your Mechanics’ Institution, where

—“words of learned length and thundering sound Amaze the _operatives_ rang’d around,”

it may have sufficed. But when held up as a criterion by which the public mind is to take its tone for my condemnation, I am compelled to pronounce it philosophy of which its author ought to be ashamed.

These evidences being all of dates several years anterior to the period when Mr. Badnall states the idea of his “Undulating Railway” first occurred to him, I shall be liable to no charge of proposing to avail myself of momentum _in consequence_ of his having proposed “_Undulating_ Railways.”

* * * * *

* * * * *

J. S. HODSON, Printer, 15, Cross Street, Hatton Garden.

FOOTNOTES.

{4a} I have known a barge of (apparently) fifty tons burthen, come up the whole length of your canal, with nothing but fourteen tons of coal to land at your basin.

{4b} In his Report on the Liverpool and Manchester Railway, Mr. Walker states the price of the 40,000 tons of coal, which he supposed might be required for the locomotive engines, at 5_s._ 10_d._ per ton. The 25,000 tons which he supposed might be required for the stationary engines, he states at the price of 2_s._ 6_d._ per ton.

In their review of this Report, Messrs. Stephenson and Locke state the price of coal at 4_s._ 6_d._ per ton for 37,222 tons.

{5} The capital requisite to complete this railway was first announced to be a million and a half. Then it was raised to two millions. Then it was raised to three millions, in order to admit of a “quadruple line” (that is, eight lines of rails,) being laid down. And credit is now taken for its _cheapness_, because, after announcing that three millions would be sufficient to lay down a “quadruple” railway, two millions and a half are stated as the _estimated_ expense of a “double” railway. That is, after having, by advertisement upon advertisement, announced that three millions would be enough to lay down eight lines of rails, credit is taken for finding out that four lines will cost two millions and a half: when the fact is, that the estimated expense is reduced only one-sixth, while the work which said three millions were stated to be enough to do, is reduced one half. In other words, twopence-halfpenny is charged for _half_ the loaf, after it had been, in every possible way trumpeted forth, that the _whole_ loaf would be sold for threepence: while even this twopence-halfpenny is liable to additions such as the following pages advert to.

{6} I believe that the average width is not the half of 66 feet: and that it is, in parts, _much_ less than half, is proved by various circumstances; one of which is the following account of an “Accident on the railway.—An accident fatal to a poor man named Thomas Ryans, took place on the railway on Monday last. Ryans was employed by the Railway Company as a breaksman; and was engaged in his business on a small train of goods drawn by the Vulcan engine. When within a short distance of a bridge, he, for some purpose, projected his head over the side of the waggon, and, melancholy to relate, it came in contact with the buttress of the bridge. The poor fellow’s brains were knocked out on his cheek; but he lingered some time before death ended his sufferings.—_Manchester Courier_.”—_Morning Herald_, 27th Sept. 1831.

{8} Mr. Badnall’s recent patent may make it advisable to state that this paragraph, as well as the far greater part of the Letter, was written prior to, and got ready for delivery at a meeting of the Kensington Canal Company, which was fixed for the 26th of September, 1832. Owing, however, to this meeting having been deferred, _sine die_, by an advertisement in the _Times_ of the 21st of that month, opportunity has been given for additions; though the paragraph to which this note refers, has neither been added to, nor altered, since it was first written.

{10a} The decision of the Committee reported to the House of Lords, was, that “It does not appear to the Committee that the promoters of the bill have made out such a case as would warrant the forcing of the proposed railway through the lands and property of so great a proportion of dissentient landowners and proprietors.”

{10b} “The London and Birmingham Railway, in seeking an act, spent 50,000_l._: and, as they did not get the act, that sum was lost to them.”

Mr. Hodgson’s speech, at the Liverpool and Birmingham Railway meeting, held at Liverpool on the 21st of September last.

{11} 488_l._ per mile, per annum.

{13} Vide Grahames’ Letter to Wood on Chapter IX. of his Practical Treatise on Railways: and his “Letter to the Traders and Canal Carriers, on the Navigations connecting Liverpool and Manchester.”

{14a} This allusion is to the number of miles between Brighton and London: which was the _comparative_ length of what they saw.

{14b} Member for Lewes, and principal ground landlord of Brighton.

{14c} Baronet and magistrate for the county.

{14d} Vicar.

{14e} Curate.

{18} This word “cylinder” means the tunnel.

{20} That is, between three and four hundred thousand gallons.

{22a} That is, 11.3 feet in diameter.

{22b} In the best of the large stationary engines now made, a bushel of coal will do the work of 44 horses for an hour. Therefore to make a current of air which should be capable of conveying 10,000 tons 100 miles in an hour, would require 43 bushels of coal: which is not twice so much as some steam vessels burn in the same time.

{26} The proposed London and Birmingham Railway is to be sixty feet wide in the narrowest places; notwithstanding that it is to have only the same number of lines of rails which you must have; while, in some parts, it will be between two and three hundred feet wide. The average width of its _whole_ line will be 92 feet.

{29a} An idea of the amount of these cuttings and embankments may be given by the following statement. Every one remembers what our school days taught us, relative to the “Great Pyramid:” the many years it was in building: the multitudes of workmen employed: and the vast sums expended to supply those workmen with merely “garlic and onions.” The excavations of the Liverpool and Manchester railway, would, if put in one lump, have formed a mass larger than that of the “Great Pyramid:” its cubical contents being only 2,983,263 yards; while the excavations for that railway amount (according to its treasurer’s statement) to 3,405,000 cubic yards: or 11,386,899 cubic _feet_ more than the whole mass of the “Great Pyramid.”

{29b} “A locomotive engine of ten-horses power will draw 120 tons at the rate a draught-house generally travels; or 50 tons at the rate of six miles an hour. I may here remark that the rate of travelling may be increased to surpass that of mail coaches; and that the locomotive engine will as readily convey 25 tons (including its own weight) at the rate of twelve miles an hour, as double the weight in twice the time.”—Mr. Jessop’s Second Report to the Committee of the Proposed Railway from Cromford to the Peak Forest Canal, at Whaley Bridge. Dated 29th November, 1824.

“An engine of four horses’ power, employed by Mr. Blenkinsop, impelled a carriage, lightly loaded, at the rate of ten miles an hour; and when connected with 30 coal waggons, each weighing more than three tons, it went at about one-third of that pace.”—_Observations on a General Iron Railway_, _by Thomas Gray_. 1825.