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595,264 · Ewen · "Figured Prism-Light" · Page 2 Home  > Prism Glass  > Patent Index  > Page 2

595,264: 2 of 6

wavy effect their areas are so small and the effect is so much interrupted by the design proper that the wavy effect is not noticeable. In the fourth place the distortion of the receiving-surface is almost entirely prevented in the process of forming the prism-light. This is probably brought about in the following manner: When the plunger descends on the receiving-surface, it chills and slightly cools such surface. When the plunger rises, the depressed or lower surfaces of the receiving-surface being nearer to the inner and heated glass are remelted, but the raised portions of the design being farther therefrom and exposed on three sides are not remelted and they serve as a sort of grid to hold the molten parts in position and keep them from running or changing form, and thus the imperfections of the receiving-surface above referred to and which are so common in ordinary prism-lights are to a great extent obviated. If any such imperfections nevertheless do exist in the finished product, they are obliterated and their effects destroyed by the presence of the raised lace-like design. In the fifth place the upper or outer surface of the raised portions of the design, since they do not appear to melt when the plunger is raised, do not become glazed, and hence all that surface is free from the glazed effect. In the sixth place, by distributing over the receiving-surface of the prism-light a design such as described the contraction and expansion of the prism-light, both while being formed and when finished, is more uniformly distributed and the various strains within the glass are accommodated for in such way as to greatly prevent or diminish the breakages. In the seventh place the shear-marks, which are almost invariably found on the so-called "receiving-surface" of the prism-light and which result from the action of the shears in clipping or cutting off the molten glass as it runs into the mold are, if not obliterated, at least broken up and distributed in such a manner by the design as to be imperceptible, or at least not offensively present, which is the case when they appear upon the extended smooth surface. In the eighth place the difficulties and disadvantages incident to the varying quantity of glass in the mold are obviated. In forming devices of this kind the molten glass is put into the mold and the operator cuts off the running stream when, in accordance with his trained judgment, a sufficient quantity of glass has entered the mold, but obviously he never can twice cut off exactly the same amount and irregularity in the size, shape, or appearance of the finished product must result from this variation in the amount of glass. This commonly appears in the surface and distorts or disfigures it. Now with this design as suggested the excess of glass in the mold is carried as an overflow into the figure or into the several raised surfaces and does not appear in any offensive or disfiguring manner. It is practically obliterated.

In like manner, if the glass is less than the required amount the irregularity is lost in the design. I have not attempted, of course, to show any considerable number of forms of my invention. I have, however, illustrated it, as it were, diagrammatically, so that it can be understood.     Figure 1 is an elevation of a prism-light, showing a design formed of raised thread-like glass portions. Fig. 2 is a section therethrough on the line 2 2 of Fig. 1. Fig. 3 is a section of a similar prism-light where the design is formed by sinking the grooves. Fig. 4 is a plan view of a prism-light where the receiving-surface has no design, but is more or less irregular. Fig. 5 is a section therethrough. Fig. 6 is a view of a series of prism-lights associated together and showing a design so formed as to be carried over a series of such lights, the lights being incorporated together by a frame so as to form a prism-plate.     Like parts are indicated by the same letters in all the figures.     A is a prism-light having the body portion B, the prisms C, the raised design elements D D, or the sunken design elements E. F is the receiving-surface when no design is used. G G indicate irregularities thereon. J J are prism-lights having the design, as indicated. Of course these designs are merely illustrative and the design may be almost infinitely varied and can be greatly changed from time to time, as taste may dictate. When the design is so formed, all the objects above referred to will be attained. The wavy effect will disappear, the receiving-surface imperfections will either disappear or be negligible, the top surface of the design will not be wavy, the design will have a lace-like appearance, the glass of the lower surfaces when remelted after the lifting of the plunger will be held in place by the grid-like elements of the design, and the design when viewed from the prism side will have soft lines and be variable as the observer moves about. The excess or insufficient amount of glass in the mold will produce no unsatisfactory appearance, because it will be lost in the design and the marks of the shears will not appear to disfigure the receiving-surface.     Of course the prism-light can be of different size, thickness, and shape from that shown, but the preferred form is one which is substantially rectangular and substantially flat and having dimensions of a few inches each and which is comparatively thin and made of clear and brilliant glass. I do not wish, however, to be limited to these particulars, for, as above pointed out, my invention may be incorporated under other conditions. I have spoken of the "receiving" side and the "prism" side. Of course the light can be received from the prism side, but under ordinary conditions the smooth side is accepted as the receiving side, and it is with this understanding that I use the term "receiving" side.