ing the metal, but in causing it to flow together, or "upset," in a circumferential direction, while at the same time it is flowing further apart, or stretching, in a radial direction. Thus treated, its thickness remains the same, except in some cases, where it is subjected to a combined operation-" broaching" and "drawing"-as happens in some of the operations of cartridge-making, etc. This broaching consists in squeezing the metal thinner, by having the space between punch and die less than its original thickness.

As what is known as the drawing-process may not be familiar to all, I will briefly describe it, in its simplest form, as used for drawing a flat disk of sheet-metal into a cylindrical or cup-like

shape. The operation consists in holding this disk so tightly between the two parallel flat annular surfaces of the dies that it cannot wrinkle, while the punch which gives it its interior form is pushed down, through a hole in the upper die, into a recess in the lower die, which fits it with the proper amount of looseness to give space for the metal between. A set of these dies is shown in Fig. 1, in vertical section through their axis. In Fig. 2 is shown an axial section and a top view of the disk of metal, technically known as a "blank,' before it is drawn. In Fig. 3 are shown the same views, respectively, at a later stage of the operation, when it has been drawn

to about one-third of its final depth. In Fig. 4 it is shown at, say, two-thirds depth, and in Fig. 5 as completed. Four small dots will be noticed in Fig. 1, marked upon the blank, and forming the corners of a square, with its diagonal placed in a radial line. In the subsequent figures it will be noticed that two of these dots, upon either side of this imaginary radius, have gradually approached each other, while the other two dots, lying in the radial line, have receded, thus beautifully illustrating the respective directions in which the molecules of the metal have travelled in reaching their new locations. In Figs. 6, 7, 8 and 9 are shown a set of dies, and the work in its several stages, of a form conical rather than cylindrical.

The dies as shown in Figs. 1 and 6 are made so that they cut the disk from a large sheet of metal at the cutting-edges, c and c', as the upper die, U, descends to perform its mission of holding the blank from wrinkling between its lower flat surface, and the corresponding flat surface of the lower die, L. When U has descended until it is firmly in contact with the blank, it stops and remains rigidly in posi tion until the punch, P, has descended and drawn the metal from between the two holding-surfaces, over the rounded corner, d, and down below 8, into its desired shape. The lower edge of the working-part of the die, 8, is called the "stripping-edge," and is kept quite sharp,

so that the metal will not be pulled up again by the friction of the punch. Although it has just passed through the die, its elasticity expands it very slightly, so that this stripping-edge is usually found

In practice it is found necessary to put an ample vent-hole for air through the punch, or else the cup is pulled up afterward by suction, in spite of the stripping edge. In one of the sample cups shown, the vent-hole was insufficiently large for aluminum, although it had worked all right with tin-plate. This difference was owing to the stiffness of the latter material. The aluminum, being softer, was pulled up by the air-suction just before the punch left the cup. This, of course, would not have happened had the press been running at a slower speed. The dies shown will do equally well for blanks which have been previously cut elsewhere. In some cases, instead of the cutting-edges, c, c, a mere rim, with a rounded corner, projects above the surface, serving as a gauge to locate the blank centrally when it is thrown in.

In Fig. 10 is shown a pair of "deepening-dies," so-called, which take a cup, Fig. 11, that has already been drawn in dies, like Fig. 1, to as great a depth as the metal will stand, and deepen it to the form shown in Fig. 14. The successive intermediate stages of the operation are shown in Figs. 12 and 13. These and subsequent similar processes are the ones used in cartridge-drawing, except that the metal is usually somewhat thicker than the space between the punch and die, so that it is also subjected to a stretching process similar to wire-drawing. This reducing in thickness is often called "broaching," but there is considerable confusion of terms used by various manufacturers.

The presses used for all the dies just described are, of course, of special construction, being made with an "inner" and an "outer' ranı. The latter carries the upper die and is arranged to stop for a time, after a part of the stroke has been made, while the inner ram, carrying the punch, descends to the bottom of its stroke and rapidly returns, just as does the ram in an ordinary single-action press. In Fig. 15 is shown a small drawing-press for work of this kind which will explain itself. It is a picture of a German press, and shows fairly well the principle involved. There are several kinds made in America, of better design, of which it might seem invidious to show one without the others.

A fuller account of this interesting process, together with rules for the construction of the tools used and a description of the products obtained, may be found in a lecture which I had the honor to deliver before the Franklin Institute, and which was published in its Journal for November, 1886.

In general, I can say, with regard to the drawing of aluminum,

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that, as far as my experiments have gone, it seems to be excellently adapted to be drawn into a great variety of household utensils, parts of scientific instruments, ornamental hardware, cartridge-shells and for very many other purposes, some of which we, probably, can scarcely conceive of as yet. One of its great advantages is, as before intimated, its capacity of working without frequent annealing. In the imperfect trials made at our works, in dies which were not especially prepared for it, it seemed to work (outside of the nonannealing) about the same as soft brass, but in some cases was not quite as tough. It, of course, did not show as well as tin-plate in regard to tensile strength. As far as I can now judge, it may be said, generally, that it is well adapted for deep drawing, and that the success of any given shape and proportions will, in comparing with other metals, be directly proportionate to tensile strengths. This view, however, may be somewhat modified in future, as the result of more careful and accurate experiments.

Since the foregoing paragraphs were written, I have seen some "drawn work" that Mr. Hunt had made, which is larger than any for which I happened to have dies on hand. Among his specimens are a sauce-pan and a tea-kettle, which corroborate my impressions as to the perfect adaptability of aluminum to the making of deep, seamless utensils,-which will open to the housekeeper a new era of healthfulness and cleanliness in the cuisine.

ALUMINUM IN SEARCH OF A NICKNAME.

BY OBERLIN SMITH, BRIDGETON, N. J.

(Washington Meeting, February, 1890.)

THE object of this paper is not so much reformatory, as historical and prophetic. History tells us that, for several months past, aluminum has, in one of its largest American manufactories, been freely nicknamed "Al" by everybody connected therewith, simply because its Christian name is too long for frequent speaking and writing. In another prominent factory, for the same reason, it is spoken of by its chemical symbol merely, pronouncing it "aye ell." These facts will, perhaps, explain the use of the final word in my title, which might otherwise seem undignified in a paper of this kind.