Besides the advantage of the vessel being unaffected by waves, since its submerged portion travels far below them, the inventor claims that it will meet less resistance from the water than would a vessel of corresponding volume sailing on the surface. It will make faster progress, because it has no waves to mount and descend; and hence it always travels in a nearly right line. The screw being submerged at a great depth will not tend to turn the vessel from her straight path. The platform being easily detachable may serve as a raft in case of injury to the submarine boat. For fast travel, on lakes, rivers, and shallow water generally, M. Tommasi proposes to support his platform on two floats which rest on the surface of the water. No weight, therefore, is thrown on the submarine vessel, which need be constructed with only just enough buoyancy to sustain itself and its engine. In this way, the upper craft has no engine or other load than its cargo; and as it merely rests upon the surface, the inventor thinks that it will skim over the same like an ice boat on ice.
For war purposes, the hemi-plunger is especially adapted, because the vulnerable portions, engines, boiler, rudder, etc., are wholly out of the reach of shot. Guns are mounted on the platform, which thus becomes a circular or elliptical turret, just above the water when the vessel is in fighting trim. Instead of steel armor, M. Tommasi has a new invention which he calls hydro-metallic plating. He reserves the details of this for future publication; but generally the armor consists of tubes in which liquid is forced under a pressure equivalent to the resistance, say, of forged steel. He thinks this will oppose shot as effectually as the solid metal, and will have the additional advantage of superior lightness.
In-soles saturated with salicylic acid have been introduced as a remedy for perspiration of the feet.
Supreme Court Patent Decision.
A United States patent was granted May 23, 1854, to John Myers and Robert G. Eunson for a wood-sawing machine for cutting boards into thin stuff for making picture frame and mirror backs. One of the principal claims was for the employment of two deflecting plates, one on each side of the circular saw, by which both sides of the sawed stuff, as fast as it was cut, was slightly deflected so as not to bind upon the saw. Suit was brought by the patentee against Dunbar and Hopper for infringement, and judgment was given in favor of the patentees, in the United States Circuit Court, this city, the damages awarded being $9,121. The defendants thereupon took an appeal to the Supreme Court of the United States, which tribunal has reversed the finding of the Circuit Court and dismissed the complaint. It was held by the Supreme Court that, inasmuch as the use of a single deflecting plate was old, well known, and in common use, it was simply an exercise of ordinary mechanical skill, and not a patentable invention, to employ a second deflecting plate, although the superiority of the double deflectors, for certain kinds of work, appears to be conceded.
Planing Mill Machinery.
The planing machine, next to the saw, is perhaps the most important agent for the conversion and manipulation of wood in use; and before proceeding to consider it, in its present form, says the author of this article, Mr. F.H. Morse, in the Northwestern Lumberman, it may not be out of place to notice briefly its origin and history.