JAR RINGS.

The old fashioned way of making jar rings was first to take a large mandrel and wrap it around with a sheet of compounded rubber until the thickness of the ring was secured.  It was then held in place by a further wrapping of cloth, vulcanized, put in a lathe and cut up into rings by hand.  That manner of procedure, however, was too slow, and it is to-day done almost wholly by machinery.  For example, the rubber is squirted out of a mammoth tubing machine in the shape of a huge tube, then slipped on a mandrel and vulcanized.  It is then put in an automatic lathe and revolving swiftly is brought against a sharp knife blade which cuts ring after ring until the whole is consumed, without any handling or watching.—­India Rubber World.

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HOW ENAMELED LETTERS ARE MADE.

The following is a description of a brief visit by a representative of the Journal of Decorative Art to the new factory of the Patent Letter and Enamel Company, Ltd., situate in the East End of London.

The company have recently secured a large freehold plot in the center of the East End of London, and have built for themselves a most commodious and spacious factory, some hundreds of feet in length, all on one floor, and commanded from one end by the manager’s office, from whence can be seen at a glance the entire premises.

The works are divided into two large compartments, and are lighted from the roof, ample provision being made for ventilation, and attention being given to those sanitary conditions which are, or should be, imperative on all well managed establishments.

We first explore the stockroom.  Here are stored the numerous dies, of all sizes and shapes, which the company possess, varying in size from half an inch to twelve or sixteen inches.  Here, too, is kept the large store of thin sheet copper out of which the letters are stamped.  Our readers are familiar with the form or principle upon which these letters are made.  It is simply a convex surface, the reverse side being concave, and being fixed on to the glass or other material with a white lead preparation.  When these letters were first made, the practice was to cut or stamp them out in flat copper, and then to round or mould them by a second operation.  Recent improvements in the machinery, however, have dispensed with this dual process, and the stamping and moulding is done in the one swift, sharp operation.

The process of making an enameled letter has four stages—­stamping, enameling, firing, and filing.  There are other and subsequent processes for elaborating, but those named are of the essence of the transaction.

STAMPING.

The stamping is done by means of presses, and is a very rapid and complete operation.