As The Skin Absorbs No Moisture, These Boats Gain No Weight By Use, And, Having No Moisture To Give Off When Out Of The Water, They Do Not, Like Wooden Boats, Show The Effect Of Exposure To The Air By Leaking.

They are, therefore, in this respect always prepared for service.

The strength and stiffness of the paper shells are most remarkable. To demonstrate it, a single shell of twelve inch beam and twenty-eight feet long, fitted complete with its outriggers, the hull weighing twenty-two pounds, was placed on two trestles eight feet apart, in such a manner that the trestles were each the same distance from the centre of the cockpit, which was thus entirely unsupported. A man weighing one hundred and forty pounds then seated himself in it, and remained in this position three minutes. The deflection caused by this strain, being accurately measured, was found to be one-sixteenth of an inch at a point midway between the supports. If this load, applied under such abnormal conditions, produced so little effect, we can safely assume that, when thus loaded and resting on the water, supported throughout her whole length, and the load far more equally distributed over the whole frame, there would be no deflection whatever.

"Lightness, when combined with a proper, stiffness and strength, being a very desirable quality, it is here that the paper boats far excel their wooden rivals. If two shells are selected, the one of wood and the other with a paper skin and deck, as has been described, of the same dimensions and equally stiff, careful experiment proves that the wooden one will be thirty per cent. the heaviest. If those of the same dimensions and equal weight are compared, the paper one will be found to exceed the wooden one in stiffness and in capacity to resist torsional strains in the same proportion. Frequent boasts are made that wooden shells can be and are built much lighter than paper ones; and if the quality of lightness alone is considered, this is true; yet when the practical test of use is applied, such extremely light wooden boats have always proved, and will continue to prove, failures, as here this quality is only one of a number which combine to make the boat serviceable. A wooden shell whose hull weighs twenty-two pounds, honest weight, is a very fragile, short-lived affair. A paper shell of the same dimensions, and of the same weight, will last as long, and do as much work, as a wooden one whose hull turns the beam at thirty pounds.

"An instance of their remarkable strength is shown in the following case. In the summer of 1870, a single shell, while being rowed at full speed, with the current, on one of our principal rivers, was run into to the stone abutment of a bridge. The bow struck squarely on to obstacle, and such was the momentum of the mass that the oarsman was thrown directly through the flaring bow of the cockpit into the river.

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