Reporter's Statement of the Case 92 C. Cls. preferred hull outline which the inventor states gives a variety of advantages. There is no bulkhead, outer skin, or blister element in the construction shown in this patent. The publication "Transactions of the Institution of Naval Architects," Vol. XIII, dated 1872 (defendant's exhibit No. 11), contains a drawing and description of a structure for the protection of vessels against torpedoes, by J. N. Moerath, Chief Engineer, Austrian Navy. Page 2 shows a ship's hull encased in armor b-b below the water line. To this armor is bolted sheet-iron plates C-C and sections (a) constructed of sheet iron riveted together to form compartments. These compartments (a) are filled with cork shavings and hydraulic chalk mixed with silicate of soda, and extend over the sides of the vessel down to the keel, covering the bottom. This publication shows and describes a blister-like structure completely surrounding the sides and bottom of a vessel. There is no central longitudinal recess in the bottom of the blister or covering for the ship. The publication styled "Transactions of the Institution of Naval Architects," Vol. LXI, published in 1919, pages 89-91 (defendant's exhibit No. 12), contains an account by Sir Phillip Watts, K. C. B., F. R. S., LL. D., D. Sc., of the means employed to protect ships from torpedo attack. The publication illustrates in Fig. A, a cross section of a warship with the bulge or blister attached. Referring to the drawing, A B C, indicates the bulge or blister, A D the side of the ship above the blister, the unbroken line D A extending down to the bottom of the ship represents the entire side. The bottom of the ship has no reference letter. The Fig. A depicts to one skilled in the art of naval construction, the outline, form, and general relation of the blister to the hull. The letter A shows the point of attachment of the blister above the water line of the hull and extending downwardly over the ship's side to a point near E where the blister joins the flat bottom. There is no inwardly extending recess in the bottom of the vessel located centrally in the hull. 316 Reporter's Statement of the Case 23. The prior art patents and publications set forth in finding 22 establish the fact that more than two years prior to the application date of the patent in suit, June 14, 1923, the use of blisters exterior to the hull of a vessel for protection from the explosive effect of torpedoes and mines was well known to those skilled in the art of naval warfare. That such blisters or bulkheads included structures entirely surrounding the bottom and partially covering the sides of the hulls to which they were attached. That the blisters were in many cases compartmented and used for storage reservoirs for fuel or water. Instances of disclosure in the prior art whereby increased buoyancy of the vessel and decreased draft are obtained by the addition of blisters are manifest. An example strikingly similar to the plaintiff's hull form is protrayed in Figs. 1 and 3 of the British patent to Von Köppen (defendant's exhibit No. 1), wherein a wedge-shaped bow portion, a bottom rising from the bow to the stern and the bottom inwardly recessed into a central canal or channel (See Figs. 3 and 5) is disclosed. During the period involved the defendant was engaged in “modernizing" its fighting ships. This consisted in making such changes in their construction generally as were deemed advisable in view of the state of the art with reference to such vessels. Among these changes were the addition of blisters to the sides of the hulls, changes to use oil as fuel instead of coal, and replacing old boilers with new. The evidence shows that in the case of two vessels, the battleships "Florida" and "Arkansas," there was a slight increase in the speed after modernization but it fails to show just what changes were made in the vessels besides the addition of blisters. Taking the evidence as a whole it fails to show the increase of speed was caused by the addition of blisters and there is no satisfactory evidence to explain how or why the addition of blisters would increase the speed of the vessel. 24. Plaintiff's patent rests upon a combination of the features stated in its claims. The defendant made no use of such a combination, or of any element thereof, except by the addition of blisters or bulkheads to the sides of its Opinion of the Court 92 C. Cls. vessels, a feature that was old in the art of constructing naval vessels, and consequently no infringement of plaintiff's patent is shown. The court decided that the plaintiff was not entitled to recover. GREEN, Judge, delivered the opinion of the court: This suit is brought by the plaintiff to recover damages for the alleged infringement of Patent No. 1,599,311, granted to the plaintiff September 6, 1926, for a marine vessel, upon an application originally filed June 14, 1923. The petition alleges infringement because of the application to certain warships of the United States of a structure extraneous to the original hull of the ships and placed thereon primarily for protection against torpedoes. The structure used serves as a protective armor and in this country is generally referred to as a "blister" or "blisters," although sometimes called "bulges," and plaintiff's counsel terms it a "bulkhead." These blisters, as used on defendant's vessels, comprise an outer metallic shell shaped for adjustment to the sides of the vessel, leaving an air space between the outer skin and the hull. The upper edges were secured to the hull a suitable distance above the water line and at the lower edges were attached to the region of the ship known as the "turn of the bilge," which is where the ship's sides join the bottom. In the particular case before us this additional protection was placed on the ships after they were built and in commission, and covered the most vital portions of the hull upon the sides, but did not in any case extend under or surround the bottom of the normal hull. They were streamlined fore and aft, and so constructed as to interfere as little as possible with the operation of the ship. The plaintiff's patent in suit is for a marine vessel constructed, as to the hull, in accordance with its claims and does not rest upon any one claim alone. Four claims are made in the patent, the last three in connection with the first and including it. These claims are as follows: 1. A marine vessel comprising a hull, and a longitudinal laterally extending exterior bulkhead structure 316 Opinion of the Court thereon surrounding the bottom and part of the sides of said hull, said bulkhead structure having a bottom rising from its bow end to its stern end, said bottom being shaped to provide a longitudinal and inwardly extending recess. 2. In a marine vessel according to claim 1, the bottom of said bulkhead structure merging into the bottom region of the bow portion and the bottom region of the stern portion of said hull. 3. In a marine vessel according to claim 1, the bottom of said hull being substantially flat throughout the midship body. 4. In a marine vessel according to claim 1, said bulkhead structure extending over part of the bow portion and the midship body of said hull. The defendant contends that the patent in suit is invalid, but even if valid, is not infringed, and any use made by the defendant of the so-called blisters or bulkhead structure is, so far as any rights of the plaintiff, or the rights of anyone else, are concerned, justified by the prior art open to the free use of the entire public. The evidence was submitted to a Commissioner of this court and the findings made by him are substantially to the effect that the government structures complained of do not correspond to the claims of the patent in suit and therefore there is no infringement. The plaintiff excepts to these findings, the effect of which would be to deny any recovery and make it unnecessary to determine whether the patent accomplished anything useful and was valid. The main issue in the case is as to the correctness of the findings, and this has made it necessary for us to consider the testimony introduced before the commissioner. The argument made on behalf of the plaintiff, and the exceptions it takes to the report of the commissioner are so voluminous that if we reviewed each feature thereof in corresponding manner the opinion would be unduly extended. As we view the case this is not at all necessary as the judgment of the court must be controlled by its conclusions with reference to a few facts which are vital to plaintiff's case. A study of the evidence taken before the commissioner of the court satisfies us that the findings made are substantially correct. We have made some changes in ver Opinion of the Court 92 C. Cls. biage in the interest of clarity, and to avoid some of the objections made by counsel for plaintiff upon matters which we consider nonessential. There is attached to the patent, and referred to therein, explanatory drawings showing diagrams of the hull of the vessel constructed in accordance with the specifications of the patent. These drawings are reproduced on a smaller scale and inserted in the findings under the caption "Patent Drawings." The argument made on behalf of the plaintiff assumes that the patent is a combination of the features described in the claims and specifications. It appears to us rather as an aggregation, each feature having its own specific functions independent of the others but it is not necessary to rest the decision on this point as the findings show definitely that the defendant made no use of such a combination as is described in the specifications of plaintiff's patent. There are two outstanding features of plaintiff's patent as shown by its Claim No. 1. First, that it comprises a "bulkhead structure surrounding the bottom and part of the sides of said hull, the bulkhead structure having a bottom rising from its bow end to its stern end" [Italics supplied], and Second, "said bottom being shaped to provide a longitudinal and inwardly extending recess." There can be no question under the evidence but that the "blisters" used by defendant did not surround the bottom of the hulls of its vessels or cover any appreciable part of it, and the findings so state. Also it appears that in the structure of defendant's vessels the bottom had no bulkhead structure, and did not rise from its bow end to its stern end, there being merely a rise at the stern to make room for the propellers. It further appears definitely from the findings that the bottom of the hull of defendant's vessel was not shaped to provide a longitudinal and inwardly extending recess. Plaintiff complains because the findings state that this last provision requires that the recess should be centrally located. We do not regard this of special importance because the evidence shows that the only recess on the hull of the "Mississippi" and other vessels of de |