One of the principal objections to sliding sashes in shop windows, is the ne cessity in most cases of making a broad casing for the Mance weights to past up and down, which excludes the light, and so much space for the exhibition d goods, and is besides unightly, according to the prevailing taste matters. To obviate these objections, eliding sashes have sometimes been non with a long train of pulleys and lines, to carry the weights to a distant salmis, where there would be the least incumbrance. Mr. Lockart, of Poland-sheet, bas however ingeniously contrived to place the weights in a horizontal positica above the window, which is a very convenient situation, and the means adopted toe that purpose are calculated to work well. Fig. 1 in the annexed sketches represents an elevation, and Fig. 2 a plan, the corresponding lettters in each referring to similar parts. a is the upper sash dosed ; 1 the lower sash partly opened ; a the weight to the upper window ; o the weight to the lower window ; e e are the pulleys on which the lines run. The dark space above the window has been drawn toe large in proportion to the other parts, but with the view of showing the arrangement more clearly. When the lower sash 1 is pulled down, the weight o is drawn close up under the pulleys, the curved pieces being ant out i of the weights for that purpose. When the upper sash a s brought down, the weight a is drawn up close to the pulleys.
To arrange these several parts to act properly, it will be necessary to observe the depth of the casing above the window, where the weights are to move • if that be (for instance) the fourth part of the range of the sashes in their grooves, then the pulleys on which the lines that suspend the sashes are coiled, must be four times the diameter of their axes, that take up the lines from the weights. As by this arrangement, the weights only move through a of the space of the sashes in the same time (by the cords passing round showing these relative proportions,) it follows that the weights must CIO; times the weight of the sashes to balance them; to save space, the weights should be of lead. By arrangement it will observed that there is only one case for the weights ifistead of two and that the situation above the window is more convenient for repair than at the sides. For pastry-cooks, butchers, and market shops generally, this improvement abr. great convenience and advantage.
Mr. Thomas Prosser, an architect of Worcester, patented, in 1880, "certain improvements in the construction of window-sathes, and in the mode of hanging the same," which appear to us deserving the attention of the reader. He proposes to attach the upper and lower sashes to the same lines which pass over a pulley attached to each side of the frame near the top of the window. These are of the kind usually called side pulleys, which have their axes at right angles to the surfaces to which they are attached. The small frames in which the
pulleys turn are movable, in dovetailed grooves, in the window-frames, and adjustable by a screw to regulate the tension of the sash lines. The two sashes are thus made to balance each other, entirely obviating the necessity for the metallic counterpoises usually employed to facilitate the raising and lowering the sashes. From this description it will be perceived that one of the cannot be moved without moving the other, so that the opening can never be made entirely at the top or bottom of the window, but an equal portion of it will be at each.
The method of attaching the lines to the sashes consists in tying neatly to the ends of the lines small pieces of metal, with longitudinal rectangular slits, which pass over T studs fixed into the sashes, with their heads across, by which the lines are secured from being accidentally detached when once they are hooked on. Instead of the beads which are generally fixed to the frame on each side of a window-sash, as guides to keep it in its place while stationary, and to preserve their perpendicular position while elevated or depressed, this patentee files a single rod into the frame, which fits accurately, into a groove in the side of the sash. This constitutes a fitting less pervious to the weather than that usually adopted, at the same time that it affords great facility in cleaning the windows ; for, as the guide-rod of the lower sash does not extend more than half-way down, so that the lower sash being elevated to the top of the window, escapes its guide-rod, and may be turned inside-out, and the upper sash being lowered to the bottom may be similarly reversed; so by this means all parts of the window can be brought within reach of a person in the room, for the purpose of cleaning or repairing.
We now p• eed to describe a mode of securing house and shop windows from the depredations of robbers, which is applicable also to doors, gates, safes, &c., which was the subject of a patent granted to Messrs. Don and Smith, of Pentonville ; and consists in the construction and adaptation of metallic shutters, arranged horizontally, in such manner that when the window or door is closed, each shutter forms a handsome panel ; and when opened, they are entirely withdrawn, and deposited behind the entablature, or in the brickwork above or below the window. The Mass likewise claim the public patronage for another property by their metallic shutters,—that of a ready conveyr sion into sun-blin ; but there will doubtless be many exceptions taken to the employment of so quick a conductor of beat, and of a material as iron, for such a purpose. But su whatever may be the ce used, the obvi ating of the necesiity of enn-blinds as a separate appendage is worthy of consideration.