The sort used is leather, made with copper rivets, and is by far the most serviceable and durable hose that I have yet seen.
Manufacturers of this article, however, for a very obvious reason, are not always careful to select that part of the hide which, being firmest, is best adapted for the purpose. Indeed, I have known several instances wherein nearly the whole hide has been cut up and made into hose, without any selection whatever. The effect of this is very prejudicial. The loose parts of the hide soon stretch and weaken, and while, by stretching, the diameter of the pipe is increased, the pressure of the water, in consequence, becomes greater on that than on any other part of the hose, which is thereby rendered more liable to give way at such places.
Hose are frequently made narrow in the middle, and, in order to fit the coupling-joints, wide at the extremities—a practice which lessens their capability of conveying a given quantity of water, in proportion to the difference of the area of the section of the diameters at the extremity and the middle part.
In order to make them fit the coupling-joints, when carelessly widened too much, I have frequently seen them stuffed up with brown paper, and in that case they almost invariably give way, the folds of the paper destroying the hold which the leather would otherwise have of the ridges made on the ends of the coupling-joints.
In order to avoid all these faults and defects, the riveted hose used are made in the following manner:—
The leather is nine and five-eighths inches broad (that being the breadth required for coupling-joints of two and a half inches diameter of clear water-way), and levelled to the proper uniform thickness. The leather used is taken from hides of the very best description, perfectly free from flesh-cuts, warble-holes, or any other blemish, and stuffed as high as possible.[M] Not more than four breadths are taken from each hide, and none of the soft parts about the neck, shoulders, or belly are used. No piece of leather is less than four feet long.
The leather is gauged to the exact breadth, and holes punched in it for the rivets. In the operation of punching, great care must be taken to make the holes on each side of the leather exactly opposite to each other. If this precaution be not attended to, the seam when riveted takes a spiral direction on the hose, which the heads of the rivets are very apt to cut at the folds. Care must also be taken that the leather is equally stretched on both sides, otherwise the number of holes on the opposite sides may be unequal. The ends are then cut at an angle of thirty-seven degrees; if cut at a greater angle, the cross-joint will be too short, and if at a smaller, the leather will be wasted. This must, however, be regulated in some degree by the number of holes in the cross-joint, as the angle must be altered a little if the holes at that part do not fit exactly with the holes along the side.
The different pieces of leather necessary to form one length, or forty feet of hose, are riveted together by the ends.
Straps of leather, three inches broad, are then riveted across the pipe, ten feet apart, to form loops for the purpose of handing or making fast the hose when full of water. The leather is then laid along a bench, and a bar of iron, from eight to ten feet long, three inches broad, and one inch thick, with the corners rounded off, is laid above it. The rivets are next put into the holes on one side of the leather, along the whole length of the iron bar. The holes on the other side are then brought over them, and the washers put on the points of the rivets, and struck down with a hollow punch. The points of the rivets are then riveted down over the washers, and finished with a setting punch. The bar of iron is drawn along, and the same operation repeated till the length of the hose be finished.
The rivets and washers should be made of the best wrought copper, and must be well tinned before being used.