One of the largest fields for copper is trolley wires, which are of great size and of many eccentric shapes.
This is merely a glimpse at the utilities that go to make up the field for Roebling wire. It is doubtful if today the company owns a complete list of the wire it has made for special and even eccentric purposes, or knows within many thousands the things that are manufactured from its wire product after it leaves the shipping room.
COATING AND FINISHING
Use determines much in the finishing of wire, and of wire rope as well, as not alone concerning the chemistry of the inside, but the covering of the outside. Material that is made for service out of doors, under water or under ground, to ensure long life needs an exposed surface more resistant to moisture than the naked steel. Copper is proof, but the pure wire is expensive for most uses and where severe strains are incurred it lacks in strength. Modern science has been too busy to recover the art of hardening copper which the ancient Egyptians lost.
Zinc, in its best application, makes steel wire weatherproof for many years and the apparently simple process of galvanizing, the fixing of a coating of zinc on the steel has multiplied many fold the utility of steel wire in places where it could ill be spared. But there is galvanizing and “galvanizing.” The first is worth the money it costs.
There are other coated wires, too. The aeroplane strands and cords are tinned. There is a bronze enamel, and a copper coating which looks as if it were applied for protection but is really the incidental result of a dip in sulphate of copper, for other purposes in the course of fabrication. The coating of wires is chiefly done in the wire works of the Kinkora Mills, though a galvanizing house is maintained also at the Upper Works. For wire that is to be made into galvanized ropes and cords, the galvanic treatment is given before it goes to be made up.
JOURNEYING THROUGH THE ROEBLING PLANTS
For exercise, a journey through any one of the Roebling plants, and especially the great Upper Works, is as good as thirty-six holes of golf. It is upstairs and downstairs, over an interminable number of thousands of square feet, through the mazes of a picture that is always changing its detail and its rate of speed, but which is all centered on one idea, to keep the stream of wire and wire rope, of all sizes, kinds and colors, moving toward the shipping room. It all seems so easy in its progress, so free from friction or any trace of confusion, that the layman does not stop to consider how many problems have bobbed up along the way of production, even of the most modest wires and rope. Wire is a trade involving intimate knowledge of many lines of business and manufacture, since the character of wire required differs in nearly all.
HOISTING FULLY COMPLETED LOCOMOTIVE WITH WIRE ROPE SLING