CHAPTER VII
THE TUBULAR SYSTEM
“Thy arts of building from the bee receive;
Learn of the mole to plow, the worm to weave.”—Pope.
ORIGIN OF THE SYSTEM
LAST year there were sounds of strife in that financial atmosphere where dwell Titan capitalists, who think and talk and dream in millions; a battle of giants, like the conflict imagined by Milton, when the satanic host levelled “triple-mounted rows” of deadly tubes with such effect against seraph and seraphim, “that whom they hit none on their feet could stand, though standing else as rocks.” But the conflict now past, concerned tubes of another kind—iron railway tubes, that seem to be the destiny of underground metropolitan travellers. The Morgan group, the Yerkes’ combination, and other great coalitions, mustered their battalions for the fray. The London County Council, following the policy of Lord Stanley’s army at Bosworth field, hovered aloof ready to take advantage of the defeat of either; the Corporation of London anxiously watched from afar; the great suburban railway companies shivered in their shoes; a parental Legislature held the balance impartially between the combatants; while the people whom the matter most concerned—some six millions of Londoners—had to sit down with folded hands and, patiently or impatiently, await their fate.
Recollecting this tangle and uproar of conflicting interests, it behoves everybody to have some notion of the subject of the Tubes and their construction.
Like many other things in the world, there is nothing new in the idea of boring a hole through the earth and lining it with brick or iron. As Pope suggests, mankind doubtless learnt the art from Nature, though the correctness of the poet’s zoological knowledge is hardly shown in the examples heading this chapter. For ages past—before London existed—that skilful excavator, the mole, tunnelled through the earth, making roads and galleries, the friction of his fur, set perpendicularly on his skin, lining his tube so that the soil did not fall in. The larvæ of the humble caddis-fly covered the inside of their cases with fine silk; and the trap-door spider lined its 12-inch long shaft with similar material to prevent the tumbling in of loose particles and to afford itself a foothold in climbing up; while the ant constructed her galleries and stuccoed them with the finest grains of soil, so that the inner walls presented a smooth, unbroken surface.
With the advent of man and his civilisation came the extensive use of furs, and in these the grubs of the moth—in the abstract the most engaging of creatures—made galleries whenever they got a chance, lining them with their own silk, wherein to undergo their transformation into the pupa stage.
Well-experienced engineers, such as the vine, beech, pine, and bark-boring beetles, are all tube-makers; but it is the pholas, or teredo navalis, who is the arch-borer, so skilled an expert in lining, that, though only the size of a quill and “soft in body,” he pierces the hard timbers of ships and quay-piles, lining the tubes as he proceeds with a saliceous substance as hard as china. The body of the Teredo is like a long white worm, varying from a foot to two inches and a half in length, and about the width of a finger. From him, it is said, the elder Brunel took his idea of the shield which he employed in constructing the tunnel beneath the Thames after the shaft had been excavated.
