5 OCTOBER 1861, Page 23

THE CHANNEL RAILWAY.* A mums book will one day be

made up of the biographies of scientific i dreamers, the strange class of men in whom the practical and the imaginative seem both to be developed, though in such unequal de- grees, who project railways to the moon but calculate the cost of balloon-sleepers to a pound, who suggest a ship canal between the Caspian and the Sea of Okhotsk but estimate the needful excavation to a yard. The list will include every variety of mental power from Paterson, whose projects were always sound and usually ill-suited to the time, down to the gentleman who wants to spend a few millions in cutting through the Isthmus of Phraa, and so enabling ships to save five days between India and China, at the cost of about three months' maintenance and an indefinite risk to their insurers, but they are all marked by an unmistakable family likeness. They are all, even 'when palpably crazed, great in detailed figures. They seem, indeed, to fancy mathematics a sort of protection, and heap up calculations to blind themselves to the delusion they half perceive. They are all magnificently contemptuous of money, but offer, nevertheless, a forty

• The Magma Railway. By James Chalmers. London : E. and F. N. Span.

per cent. dividend, and all are satirically critical on the 'wild" pro- jects which may perchance have preceded their own. To this last rule Mr. Chalmers is no exception. He runs over the list of the

men who have projected a road across the Channel with a satiric glee which, when his own pretensions arc considered, is not a little

amusing. They are twelve in number, beginning with Mathieu, an engineer, who proposed to the First Consul to tunnel under the sea- floor, and ending with Mr. Chalmers, who proposes to place a tunnel upon it. One of these projectors, M. de Is Hale, who proposed to sink cast-iron tunnels on the floor of the Straits, affirmed that the work presented no difficulty "to those who could remain during half

an hour in deep water," an assertion certainly indisputable. Another, M. de Gamond, intended to create thirteen islands, dig through them to terra fermi and tunnel right and left, and this proposition was seriously entertained by the present Emperor, while a commission of engineers recommended an outlay of 20,0001. for surveys. It was

only given up because it might interfere with navigation. A. third suggested an iron tube laid in the Channel " at a slope which would create a motion sufficiently powerful to enable the carriages to cross

the Channel without a steam-engine." This man was doubtless an engineer, and the fact that he forgot that the carriages had toget back again is a laughable illustration of the mental deficiency of his

class. The very same man who forgot half his work, went iuto de- tails about gas for the lighthouses at each end of the tube. The

next we must extract entire, as it is, we think, a nearly perfect speci- men of intellectual imbecility. The writer enters into details which prove that he must have thought out his scheme for months, and this is the result :

" To situate a tunnel at a uniform depth from the surface by means of ties below (and buoys above if necessary) at suitable intervals. The continuation of

the tunnel into the shore on either coast I should dispenre with; and in order that it should have a partial freedom of motion, it should terminate with solid ends before reaching the shores. To these points chain piers should extend ; or, if strict economy. (say in the first instance) were aimed at in this item, the com- munication might be by small steamers."

He forgot that the little steamers might run a little further and save us the expense of his railway altogether. Yet Mr. Chalmers says this is the best worked out and most reasonable plan which has ap- peared, of course previous to his own. Two other designs remain to be mentioned : " The proposer of the arched roadway or tunnel oa

the bottom, will, with 40 subaqueous boats (of which he is the in-

ventor), 1500 sailors and navvies, 4,340,000 cubic yards of material, and 10,000,000/., undertake to construct a tunnel by means of which the Straits can be crossed in thirty-three minutes; and he of the mammoth bridge will make in the Channel 190 pedestals, 300 feet square at the bottom, consisting of rocks bolted and lashed together, gradually rising at an angle of 75 deg., till they form each an insular plain, 150 feet square, 40 feet above the level of the sea ; on these, build towers 100 feet diameter, 260 feet high ; and crown the whole with a tubular bridge 50 feet deep and 30 feet wide." The last is Mr. Chalmers, who, we are bound to say, is singularly moderate in his views on expenditure and returns. He does not propose an outlay of more than twelve millions, or expect a return of more than ten per cent., and not this for the first four years. He denies, and with great justice, that the present amount of traffic diets any fair test for the traffic a railway would attract, and is indeed, on most questions of finance, moderate and sensible to a fault. But his plan is just as wild as those of his predecessors :

" The principal feature of the work is simply a strong iron tube reaching from shore to shore in the still depths of the Channel, beyond the influence of the

storms that render the sea dangerous on the surface. It is supported by its own buoyancy, having a powerful tendency to rise; and is kept down by anchors or boxes, attached to and surrounding it, and filled with rough stone, both boxes and tube being covered by an embankment of similar material; and, as the cur- rent alternates up and down Channel with the rise and fall of the tide, the silt of

the bottom carried by it against and into this embankment will fill up the in- terstices, and in a few years convert it into a solid impermeable mass, having the

appearance of a ridge reaching from shore to shore, about 150 feet wide at the base, 40 feet high, and from 40 to 120 feet below the level of low-water. In short, the materials of which this embankment will be formed, are the same as the French engineer proposed to use in forming his islands, through which he in- tended to penetrate to the bottom of the Channel."

The tube is to be built in sections, and Mr. Chalmers has prepared most careful explanations of the mode in which the sections are to be riveted together, the buoyancy of the tube destroyed, and the necessary quantum of air supplied by colossal ventilators. He pro- vides for light, and points admiringly to the prettiness of his tunnel, so different from those nasty tunnels underground ! He calculates the price of iron with the most scrupulous nicety :

"But if this work is not to form an exception to the customary mercantile rule —viz. that large orders are executed at lower rates than small ones—there is more likelihood of the iron being obtained at 25 per cent. less, than of having to

pay 25 per cent. more, than the above price of 12i. 16s. 8d. Some have expressed tears that a demand so great will disturb the market, and raise the price of iron but such fears will not for a moment trouble those who know the resources and capabilities of the iron trade. It is more likely, by giving an impetus to produc- tion, to lower prices. The quantity required will be spread over several years; and if, in its preliminary stages, the Channel Railway resembles other great undertakings, there will be ample time to make preparation for the increased demand."

He has described the precise manner in which the tubes are to be sunk, and calculated the "cohesive power" exerted upon the ends of the sections, has given estimates for paint, and suggested lights for the lighthouse, but lie has, nevertheless, forgotten two little points.

He admits that a floor must be prepared or "selected" for each length of the tube—though what selection is possible it is difficult to imagine—but he has entirely omitted to explain how the prepara-

tion is to be effected, and has allowed only two millions for preparing 264 floors of 400 feet each, to support a railway train without serious deflection over a road which rises and falls thirty feet at

a time, and to be constructed below the ocean in a sea which is the dread alike of travellers and seamen. Moreover, for the prepa- ration of these floors he has allowed exactly four days apiece, about the time it would take to get the vessels to the precise spot required. These are trifles of course to genius, but they are sufficient to prove that Mr. Chalmers, with all his acuteness, does not understand the first conditions of his own problem, and must be classed with the dreamers instead of the benefactors of the world.