New Shingle Machine.

Among the patents particularly noticed in the Commissioner's report, is one for a shingle machine, which cuts the shingles in a peculiar form. The shingles cut by this machine does not taper from one extremity to the other, but the taper is confined to about half the length of it at one end, the faces of the remaining half being parallel to each other. This shape of the shingle avoids the bending which is incident to those of the ordinary form, when nailed upon the roof—an object well worthy of attainment.

Improvement in Blacksmiths Forges.

This invention was entered at the Patent Office on the 15th instant, by James K. Hobbs. The improvement consists in the placing of grate-bars at the bottom of the fire chamber, below which is an open air chamber into which the cinders and ashes fall through the grate, instead of accumulating and clogging the fire chamber. The cinders may be drawn out of the air chamber by an opening at the side of the forge. The blast is admitted above the grate, and the mouth of the air chamber being ordinarily closed, the blast is not affected by the grate. We think it must prove a useful invention.

Improved Fire Engine.

This improvement consists in part, in the arrangement of two sets of levers and hand poles on each side, in such a manner that "when force is applied to the hand-poles of the outside levers, in a reverse direction to that which is applied to the hand poles of the inside levers, both powers will agree in forcing the pistons of the pumps in one and the same direction, while the reverse motion of the levers will prevent the engine from rocking. Entered at the Patent Office, on the 10th instant, by Barton & Button.

A simple Cheese-Press.

An ingenious mechanic, not long since, hearing some persons conversing on the ordinary cost of cheese-presses, which is generally from three to six dollars, boldly averred that he could build a cheese-press in one hour, which would answer a good purpose as such, and which might be afforded for fifty cents. Being bantered on the subject, he went to work, and by means of a good lathe and boring machine, he actually produced his cheese-press within the hour; though not very smoothly finished. We give a sketch of it at the head of this article,—too plain to require explanation. Subsequently, several others were made on the same plan.

Cast Iron Roofing.

A specimen of cast-iron plates for roofing of buildings, says the Philadelphia Ledger, has been exhibited at the Exchange, in Philadelphia, by the inventor and patentee, Mr. Wm. Beach. The plates are about a foot square, and are made to fit one into another so as to render the roof perfectly water-tight, with the application of white lead to the joints. In every respect this material for roofing is preferable to any other description now in use. As to its durability, there can be no doubt that it would remain perfectly whole for ages, if covered occasionally with a coat of paint, and even without that preservative, rust would not affect it materially for a period of fifty years at least. As compared with copper, the cost would be nearly one half, as it is expected the iron can be furnished at 16 cents per square foot, while copper would at the most moderate estimate cost 28 cents. As regards the weight of an iron roof, which at first sight would appear an objection, it is far less than one formed of slate, and does not much exceed one of copper. The iron plates weigh three and a half pounds per square foot. A slate roof would cost about eight cents per square foot, but for durability, and the ease with which it can be put on and made water tight, the iron roofing would appear to be far preferable. The plates exhibited were cast at Troy, New York, and are of the very best quality. The patent for the eastern States is now owned by Mr. Hiram Hemmistone, of Troy, in which neighborhood the adaptation of such a durable material for roofing is rapidly attracting public attention there. Starbuck's machine shop and foundry at Troy has been covered on this plan, and it has also been adopted for the roofing of an arsenal at West Point.