Up: Patent Index

156,412 · Dale · "Improvement in Vault-Covers" · Page 2 Home  > Prism Glass  > Patent Index  > Page 2

156,412: 2 of 3

inserted in the sidewalk or upon the walk itself, or upon a shelf formed therein.     In order that provision may be made for the passage of light through the device bull's-eyes E E of glass are inserted. Their form is that shown in the drawings, where it will be seen that upon the lower end of each there is a projection which nearly or quite fills the aperture formed in the frame, as shown in Fig. 1. This projection is of such length as to allow the under surface of the bull's-eye to come down flush with the under surface of the frame, while the whole length of the eye is such as to cause its upper surface to be flush with the upper surface of the upwardly-projecting flange thereof. For the purpose of more effectually securing the eyes in position they are furnished with a groove which is formed in their peripheries, so that as the cement is placed around them it shall fill such groove and thus prevent the possibility of the removal of the eye. The eyes are secured in the frame and made water-tight by means of what is known as Portland cement, or it may be by any other kind which is capable of being applied in a semi-liquid state, or of such consistency as will cause it to fill the spaces between the eye and the surrounding metal, and afterward of becoming hard, as the first-named kind will do.     The method of applying the cement is clearly shown at F F, in the Figs. 1 and 2, where it will be seen that its upper surface is even with that of the frame and the bull's-eyes, so that when the device is complete it presents an even and level surface for the people to walk upon. It will also be seen that the cement extends some distance above the upper surfaces of the transverse flanges or partitions B and B', protecting almost the entire body of the metallic frame from the rays of the sun and the effects of changes of temperature outside of the cover,

the cement being a non-conductor, or at least a poor conductor, of heat, and being applied in the semi-liquid or plastic state, renders it certain that, with sufficient care in applying it, the most minute spaces between or cavities in the parts will be filled, and that thus a water-tight vault-cover will be made which will not be affected to such an extent by the changes of temperature to which it is exposed as to cause it to become leaky by long-continued use.     I have described my improvement as peculiarly applicable to vault-covers; but it is also applicable to the roofs of buildings, the only change required being in the flanges upon which it rests, which should be so constructed as to cause them to overlap each other and have a recess for the insertion of cement in such a manner as to prevent any leakage between them.     What I claim as my invention, and desire to secure by Letters Patent, is--     1. The grooved bull's-eyes E, provided with a shoulder, e, by which they are supported on the bottom plate of the dish, and reduced ends E' fitting the apertures in the latter, substantially as specified.     2. The metal dish A A', provided with dovetailed or under-cut ribs B, which terminate some distance below the upper surface of the dish, substantially as and for the purpose specified.     3. The metallic dish provided with the inwardly-projecting ledge C, substantially as and for the purpose specified.     In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses. WILLIAM DALE. Witnesses:     D. P. HOLLOWAY,     B. EDW. J. EILS.