Full opinion text
McNAMEE, District Judge. This is an action for infringement of four patents of plaintiff, Floyd A. Firestone, Nos. 2,280,226, 2,398,701, 2,467,-301 and 2,592,134, which will be referred to sometimes hereinafter as Nos. 1, 2, 3 and 4. All of the patents relate to flaw detection apparatus and the use thereof. The Claims of the patents which it is alleged were infringed are Patent No. 1, Claims 2, 3, 4, 10 and 11; Patent No. 2, Claims 7, 16, 19, 20, 25, 26, 29 and 32; Patent No. 3, Claims 1, 2 and 3; Patent No. 4, Claim 2. The Parties The pjaintiffs are: Floyd A. Firestone, inventor of all four patents in suit and the owner of the legal title to Patent No. 1; Sperry Products, Inc., a New York corporation, the exclusive licensee under Patents 1 and 2, and the owner of Patents 3 and 4; United Aircraft Corporation, a Delaware corporation, the owner of Patent No. 2, and present here as an involuntary party plaintiff. The defendants are: The Aluminum Company of America (hereinafter called Alcoa), a Pennsylvania corporation, with a place of business at Cleveland, Ohio, where it has used the accused apparatus known as an Immerscope; and Electrocircuits, Inc., maker and supplier to Alcoa of such apparatus. Electrocireuits is a California corporation, having no place of business in the jurisdiction of this Court but became a party by the voluntary filing of an Answer and Counterclaim. The Pleadings The Complaint alleges infringement of the Claims enumerated above. The Answer denies infringement and alleges invalidity of the patents on several grounds, including alleged misrepresentations to the Patent Office, lack of invention, anticipation by prior patents and publications, ambiguity, failure to fully disclose invention and misuse of the patents. A counterclaim filed by Electrocircuits for treble damages alleges that damages were sustained by that defendant as a result of the violation by plaintiffs of the antitrust laws. The affirmative defenses alleged in the Answer and the alleged violation of the antitrust laws set forth in the Counterclaim of Electrocircuits are denied by plaintiffs. Thus, the principal issues are: Invalidity, infringement, alleged misuse of the patents and alleged violation of the antitrust laws. Preliminary Statement The devices described by the patents in suit which are sold under the trade name “Reflectoscope” are instruments that use the pulse echo ultrasonic method in the detection of flaws in metal parts. By this method ultrasonic sound waves having a higher frequency than that audible to the human ear and capable of penetrating solid, liquid or gaseous material are propagated into a metal part. The waves travel through the part at a known speed of propagation characteristic of the material of the part under inspection. When the waves reach the opposite end of the part or when they encounter discontinuities or flaws therein their echos are reflected back to the face of the part. The reflections from flaws nearest the entering end of the part arrive at that point before the reflections from discontinuities farther away and sooner than the reflections from the opposite end of the part. As these various reflections reach the entering end of the part they are amplified and by means of a sweeping motion of a beam of cathode rays they are registered on a cathode ray oscilloscope in a manner that permits the determination of the time of travel of the waves and the location of flaws in the- part. In order to measure accurately the time of travel of the waves to and from the reflecting surfaces, it is necessary to propagate them in short bursts or pulses to permit the reception of the reflected echo prior to the propagation of a subsequent pulse, hence the term “pulse echo.” In the early 1950’s Donald Erdman, a former president and founder of Electrocircuits, developed a so-called Wide Band Converter. This device had the circuitry necessary to produce ultrasonic vibrations as high as 25 megacycle frequency and the apparatus to amplify and receive the electrical impulses generated by the returning echoes. The wide band converter was used primarily for detecting flaws in parts by placing the part to be inspected under water. In 1952, when Electrocircuits was ready to place its device on the market, Richards, then president of Electrocircuits, conferred with Farwell, president of Sperry, with the view of effecting an arrangement that would enable Electrocircuits to sell its apparatus without being sued for infringement by Sperry. Richards proposed that Sperry license the Firestone patents to Electrocircuits or, in the alternative, that Electrocircuits sell its apparatus to Sperry for resale by the latter. Both proposals were rejected by Sperry. Later an agreement was reached by the terms of which Sperry agreed to permit Electrocircuits to sell its device but only upon condition that each wide band converter would be used in conjunction with a Sperry Reflectoscope. Under this arrangement the only part of the Reflectoscope that was used was the cathode ray oscilloscope. All other functions of the dual apparatus were performed by the wide band converter, the Reflectoscope being 80% useless. This arrangement was effective for but a substantially short time, after which Electrocircuits placed the accused Immerscope on the market. Some of the accused devices were sold to the defendant Alcoa and used by it in its plant in Cleveland, Ohio. This suit followed. Electrocircuits was unable financially to defend this action and entered into a contract with Curtiss-Wright Aircraft Corporation, by the terms of which Curtiss-Wright agreed to finance the defense of the litigation. As a part of this agreement Curtiss-Wright was granted the right to manufacture and sell Immerscopes upon the payment of royalties to Electrocircuits. The Immerscope is a device used primarily in underwater inspection of metal parts but it is used also for flaw detection where the part to be inspected is not submerged. It is plaintiff’s claim that the Immerscope is in all respects the equivalent of the device described in the claims of the Firestone patents in suit. Defendants direct their heaviest fire against the validity of the patents, about 80% of their voluminous brief being devoted to a discussion of that issue. Their defense against the charge of infringement is generally that the Immerscope follows the prior art rather than the teachings of the Firestone patents. Additionally they rely upon a number of separately stated grounds to avoid infringement of some of the many claims in suit. The issues raised by the defense of misuse of the patent and Eleetroeircuits’ counterclaim based upon an alleged violation of the antitrust laws have been dealt with in separate briefs. Accordingly, in this opinion the issues of validity and infringement will be discussed in that order and will be followed by an inquiry into the merits of the allegations of misuse of the patents and those relating to the alleged violation of the antitrust laws. Is Patent No. 1 Valid? Alleged Misrepresentations to the Patent Office Defendants’ first ground of attack on the validity of Patent No. 1 is based upon the claim that Dr. Firestone made misrepresentations to the Patent Office in relation to submarine sounding devices, particularly that of Langevin, et al., Patent No. 1858931, issued May 12, 1932, that induced the Examiner to approve the issuance of the patent applied for by Firestone. The application was filed May 27, 1940. By Patent Office action of August 6, 1940 several of the claims were rejected on prior art, including Langeyin. On January 18, 1941 Dr. Firestone requested reconsideration of the rejected claims, and in support thereof submitted an extensive argument in which, among other things, he delineated the critical differences between Langevin and the invention described in Firestone’s application. The Langevin invention is an apparatus for depth sounding and the location of submarine obstacles by means of ultra audible waves. It is intended for use in the ocean and other navigable waters to insure greater safety in navigation but was not designed to function as an instrument for the detection of flaws in metal parts. In his argument to the Examiner Dr. Firestone said, inter alia: “ * * * Langevin teaches- how to determine distances of several fathoms in water where the reflected wave train will be received after 10,000 microseconds or more; I teach how to determine the thickness of a piece of steel when it is even as thin as Vie inch and when the reflected wave train arrives 0.2 microseconds after the initial pulse. (I have actually done this.) The apparatus described by Langevin could not possibly accomplish such a result, no matter how much its refinement along the lines described; the errors in the mechanically operated switch, the inertia of the mechanical oscillograph, and the fact that the wave trains last as long as 'less than 3/looo second’ would make the least distance which could be detected, of the order of 10 feet or more, and even then there would be a large error in the determination.” “ * * * After study of Langevin’s disclosure, I have placed this limit at 10 feet in length his equipment would not function on pieces less than 10 feet long (if indeed it would even be satisfactory at 50 feet) and I claim as my invention the application of the reflection principle to all pieces smaller in length than 10 feet.” By action taken on February 15, 1941, the claims were again rejected on the prior art. On August 14, 1941 Dr. Firestone submitted a lengthy response to this second rejection, in which he outlined precisely and in great detail the many factors which, in his opinion, operated to render the references cited by the Patent Office inapposite. Among other things, he said: “In my last reply I tried to distinguish my invention from the submarine sounding devices, the general distinction being that, since the linear dimensions of a metal part to be inspected may be Yiooo as great as even the shallower depths of ocean to be measured, the wave train in my metal part must be Yi ooo as long, my indicating device must be 1,000 times as fast, and the synchronization of the wave emitting device and the time scale in the indicating device must be 1,000 times as accurate. The refinement of the ocean sounding device by a factor of 1000 is no mere matter of mechanical skill but requires profound novelty. Since longitudinal waves travel through about Yi inch of steel in one millionth of a second, the parts of my device must function with a consistent accuracy of a fraction of one millionth of a second.” In this second argument Dr. Firestone referred to the measurement by his apparatus of a piece of steel %6th inch as follows: “Since I have seen successive reflections in a steel plate %eth in. thick I know that my synchronization is good to Yi microsecond.” On October 4, 1941 the claims were again rejected by the Patent Office. On October 10 and 11, 1941 Dr. Firestone had interviews with the Examiner, and on October 23, 1941 he filed amended claims and, as indicated above, Patent No. 1 issued on April 21, 1942. It is contended by defendants that in the portions of Dr. Firestone’s arguments quoted above the following misrepresentations were made: 1. That by the use of his apparatus Firestone measured a metal part as thin as %oth of an inch. 2. That the submarine sounding devices disclosed by the prior art, and particularly that described by Langevin, could not measure distances of 10 feet or less. 3. That Firestone’s apparatus constituted a refinement of the depth sounding devices by a factor of 1,000. Defendants assert that these alleged misrepresentations, particularly the representation as to a refinement by a factor of 1,000, persuaded the Patent Office to issue Patent No. 1. In support of their contention that Dr. Firestone did not measure a piece of steel Y.a inch thick with his invention, defendants in their original brief relied upon a photograph of a test made by Dr. Firestone on March 1, 1940 on a Hamilton propeller blade which indicated difficulty in measuring a distance of 10 inches. They also relied upon an excerpt from a statement of Dr. Firestone’s attorney to the Patent Office in connection with the application for Patent No. 2 which reads: “Hence with the apparatus of applicant’s prior patent inspection or testing over small distances or for small parts could not satisfactorily be made.” However, as hereinafter shown, a test made on November 2, 1940 shows clearly that the evidentiary facts upon which defendants rely afford no support for their contention. In their original brief defendants raised the question that Dr. Firestone may have made the %eth inch measurement by using improvements not disclosed in Patent No. 1. The Court’s examination of the voluminous record disclosed evidence not discussed or referred to by counsel in their briefs which seemed clearly relevant to the question whether Dr. Firestone measured %eth inch of steel by using improvements not disclosed in his application. Such evidence, considered with the evidence referred to by the parties, seemed fairly susceptible of the inference that the %6th inch measurement could not have been made otherwise than by using improvements not disclosed in Patent No. 1. In the interest of affording both sides an opportunity to comment thereon, the Court wrote identical letters to counsel outlining the evidence apparently overlooked by them. It will be sufficient for the purposes of this discussion to indicate in the following paragraph the more significant aspects of the evidence referred to in the letters to counsel. Dr. Firestone’s first reference to the Ideth inch measurement appeared in his argument to the Examiner dated January 8, 1941 and received by the Patent Office on January 16, 1941. In a letter dated January 15, 1941 Dr. Firestone informed Edward Eaton of the Hamilton Propeller Division of United Aircraft that a measurement of a parallel plate %6th inch thick had been made. In this same letter Dr. Firestone stated: “This improved operation and high speed has been made possible by two improvements; first, the damping of the quartz crystal by the addition of a heavy layer of wax to its back side, and, second, the construction of a new amplifier having very short time constants in all parts of its circuit.” In Patent No. 2, which was applied for after Patent No. 1 issued, there appeared certain statements which seemed to indicate that the measuring capability of the improved apparatus of the later patent was limited to %6th inch. Testifying as a witness at the trial, Dr. Firestone stated, in effect, that shorter distances could be measured with the apparatus of Patent No. 2 than with the apparatus disclosed in the Number 1 patent. He further testified that %6th inch could be measured with Patent No. 1 by the application of the successive reflection technique disclosed in that patent. In its letter the Court noted the difficulty of reconciling Dr. Firestone’s testimony with the statements made in his letter to Eaton and the statements appearing in Patent No. 2, and suggested that counsel express their views on the relevancy and legal effect of the evidence referred to in the letter. In response the Court received two additional memoranda from counsel on each side and a memorandum from Dr. Firestone who, although a party to the action, was not represented by counsel. It would serve no useful purpose to review in detail the arguments advanced in the supplemental memoranda. Although the Court had expressed no opinion on the merits of the controversy, defendants characterized the observations of the Court as being “eminently correct” and, for the first time, the defendants contended that Firestone’s representations to the Patent Office in respect of the Vieth inch measurement were false and fraudulent. In their supplemental memoranda counsel for Sperry point out that the amplifier referred to in the letter to Eaton was an improvement within the skill of the art as taught in Patent No. 1 and that the damping of the crystal was the only improvement used in the %8th inch measurement that was not within the disclosures of that patent. Sperry also argued persuasively that although Patent No. 2 makes specific reference to a measurement of %6th inch it is nevertheless possible to measure shorter distances with the apparatus of that patent. In addition Sperry directed attention to plaintiff’s Exhibit 54 hitherto overlooked by counsel and the Court which shows that two months before his first representation to the Examiner Firestone had actually measured a parallel plate of aluminum % inch thick with the apparatus of Patent No. 1. Exhibit 54 is a written entry dated November 2, 1940 appearing on page 46 of Dr. Firestone’s notebook. It records the reflections in parallel plates of aluminum % inch to 1 inch thick by using a crystal of 4 megacycle frequency. Defendants do not deny that Exhibit 54 reflects the measurement of y4 inch of aluminum by the apparatus of Patent No. 1 unaided by any improvement. They assert merely that the recording of such test indicates that its results were unobvious and unexpected. However, the importance of Exhibit 54 cannot be minimized. The fact that the apparatus of Patent No. 1 unaided by improvements was capable of measuring y4 inch of metal is of the utmost significance in relation to the representation of Firestone to the Examiner. Sound waves travel through aluminum at about the same rate of speed as through steel. With Exhibit 54 available as evidence of the capability of Patent No. 1, it was wholly unnecessary for Firestone to represent that he had measured %eth inch of steel with the apparatus of that patent unless he had actually done so. The y4 inch measurement was alone sufficient to demonstrate the infinitely greater speed of operation of the device of Patent No. 1, vis-a-vis, the depth sounding devices cited by the Patent Office. It is unreasonable to suppose that Firestone would have deliberately cheated on a matter of fractions of an inch where there was no need or motive for doing so. Furthermore, in the light of the results obtained by using a crystal of 4 megacycle frequency as shown by Exhibit 54, it seems probable that by the use of crystals of higher frequency as taught by Patent No. 1 and by following the teachings of that patent in all other respects, the apparatus of the patent could measure distances shorter than y4 of an inch. In its supplemental memorandum Sperry demonstrates convincingly that the measurement of %8th inch is within the capability of Patent No. 1. The defendants have made no effective answer to the arguments advanced by Sperry in this regard. I am satisfied therefore that the test of November 2, 1940 does not represent the full measuring capability of Patent No. 1. The comparisons made by Firestone in his representations to the Examiner were of measurements of the order of 10 feet or more in water with measurements of the order of fractions of an inch in solids. In view of this, the slight difference between y4 inch and Vm inch cannot be considered as a material variance sufficient to have warranted the rejection of Firestone’s application. As will be shown, the measurement of y4 inch was sufficient to demonstrate the wide disparity in the respective speeds of operation of the patented device and the depth sounding devices cited by the Patent Office. It may well be that the %eth inch measurement referred to by Firestone in his representation to the Examiner was made with the improvements referred to in the letter to Eaton. But this does not alter the fact that the demonstrated capability of Patent No. 1 to measure y4 of an inch as well as its potential capability to measure shorter distances was sufficient to overcome the presumed anticipatory effect of the prior art cited by the Patent Office. I hold, therefore, that the representation of Dr. Firestone as to the %eth inch measurement was not fraudulently made and that under the circumstances such representation was not a material departure from the true measuring capability of Patent No. 1. Sperry has requested permission to demonstrate to the Court that the apparatus of Patent No. 1 is capable of measuring %sth inch of steel and proposes to make such demonstration by using only such components of the device as were available at the time the application for that patent was pending. However, for the reasons stated above, I deem such a demonstration unnecessary. The request is therefore denied. In support of their contention that the representation that Langevin’s apparatus could not measure a part of the order of 10 feet or less, defendants rely upon prior art not cited by the Patent Office, consisting of three issues of the International Hydrographic Review published, respectively, in November 1924, July 1926 and November 1938. In the first of these publications, which discussed the apparatus constructed by Langevin, it is asserted: “The return of an echo has been received distinctly from 1 meter only.” The second publication describes an echo sounder with which “soundings may be obtained in 2 feet of water or even less.” And the 1938 Review refers to measurements of a depth of 1'3" in the Thames River and a measurement of a depth of 6 inches in a test tank. Defendants do not claim that Dr. Firestone had knowledge of these tests at the time he made his representations to the Patent Office and they disclaim any purpose to impute to him a fraudulent intention in stating that Langevin’s apparatus was incapable of measurements of the order of 10 feet or less. However, they do claim that the prior art cited by them demonstrates that Dr. Firestone’s statements were erroneous. Necessarily the statements of Firestone relative to the capability of the depth sounding devices cited by the Patent Office were estimates rather than representations of facts. However, they were conservative estimates. It has not been shown that any of the depth sounding devices cited by the Patent Office could measure 10 feet or less in solid parts. All that has been shown is that on the basis of Langevin’s apparent capability to measure one meter (39.37 inches) in water Firestone overestimated the degree of refinement of his invention over Langevin, which was the best of the file wrapper references. However, if the statement in the 1924 publication that Langevin measured a depth of one meter be accepted as correct, it would nevertheless be true that Firestone achieved a degree of refinement over that reference by a factor of substantial magnitude. Sound waves travel through steel more than four times as fast as through water. The round trip travel time of such waves through 39.37 inches of water is approximately 1,400 microseconds whereas the round trip travel time of such waves through inch of steel is 2 microseconds. Thus, on the basis of the demonstrated capability of apparatus No. 1, Firestone achieved a degree of refinement over Langevin by a factor of approximately 700. This is less than Firestone’s estimate of the factor of 1,000, but the fact that the apparatus of Patent No. 1 operates at a rate of speed approximately 700 times greater than the speed of the best of the devices cited by the Patent Office is more than sufficient to sustain the burden of Firestone’s argument to the Examiner that such depth sounding devices could not operate fast enough to be used for the detection of flaws in solid parts. Computed on the assumption that the apparatus of Patent No. 1 is capable of measuring %6th inch of steel the factor of refinement would be substantially more than 2,000. The best of the depth sounding devices now cited by defendants is the Marconi echo meter, which apparently measured a depth of 6 inches in water. The round trip travel time of sound waves in 6 inches of water is 212 microseconds, or more than 100 times as slow as the round trip travel time through % inch of steel. If the Patent Office had cited the best performance of the Marconi echo device and Firestone represented that Patent No. 1 was capable of measuring % inch of steel, he nevertheless would have been able to show a refinement of his device over the best of the references now cited by defendants by a factor of 100. Otherwise stated, it appears beyond question that Firestone had actually measured a time interval over one hundred times shorter than any time interval measured by any depth sounding device discovered in the prior art. Therefore, on the basis of the strictest test that can be applied fairly, the apparatus of Patent No. 1 is more than one hundred times better in its capability to measure short time intervals than the best of the references cited by defendants. If it be assumed that the device of Patent No. 1 could measure %eth inch of steel, the refinement of Firestone’s invention over the best of the prior art would be represented by a factor of more than four hundred. There are yet other factors to be considered in determining the issue of misrepresentation. The increased speed and accuracy of the patented device was directed to the accomplishment of a wholly different object than that of the depth sounding devices. Patent No. 1 represents no mere improvement of prior inventions. It is the first and basic patent in the field of ultrasonic pulse echo flaw detection. In reliance upon its validity several additional patents covering improvements on the basic invention have been granted. Its validity has not heretofore been challenged. A substantial industry has been based upon the patent. In these circumstances it would be grossly unjust and unfair to overthrow the statutory presumption of validity solely because of the immaterial differences in the estimates and representations of Dr. Firestone. A fair analysis of the record leads to the conclusion that defendants have failed to sustain their claims of misrepresentation by that degree of clear and satisfactory proof required by law. I find that the presumption of the validity of Patent No. 2280226 has not been impaired by misrepresentations to the Patent Office. Are the Claims of Patent No. 1 Invalid because of Insufficient Disclosure? Defendants allege that the disclosures of the patent are “very meager.” They complain that the amplifier, rectifier, linear sweep and oscilloscope are shown in Fig. 1, by rectangles or a circle, and, although conceding that the circuit diagrams for the high frequency oscillator, modulator and pulse oscillator are shown on Fig. 2, they assert that no values are given. It may well be that the disclosures would be insufficient to enable a layman to understand the principle of the patent or apply the means therein described but the detailed description of the invention is clear, exact and sufficiently precise to enable one skilled in the art to make and use the invention. The statute requires no more. The correctness of the statement in the patent that the circuits as shown in Fig. 2 “will be understood by any one skilled in the art” is not questioned. The claim that no values are given is fully answered by the statement of the Court in Hazeltine Research v. Avco Mfg. Co., D. C., 126 F.Supp. 595, 599, affirmed 7 Cir., 227 F.2d 137, certiorari denied 350 U.S. 987, 76 S.Ct. 474, 100 L.Ed. 854 that: “The original Toulon Patent 2,-227,815 and the patent in suit, Re. 22,055, are not indefinite or incomplete because of the fact that they do not specify the values of various circuit elements, since such values, per se, were not a part of the invention; they were not critical ; they were well within the skill of competent radio engineers at the time the Toulon invention was made; and since it is not customary to specify values of circuit elements in the specifications of patents dealing with inventions of a system character, as contrasted to those dealing with particular elements or components of a system.” Defendants also claim that the subject matter of the claims adds nothing to the prior art. Their principal reliance in support of this contention is the 1935 Russian publication of Sokolov which they assert fully taught the echo principle of testing small parts. This contention is disputed vigorously by plaintiffs. The issue thus raised will be dealt with hereinafter in discussing the pertinency of prior art cited by defendants. Sokolov refers to a high damping decrement as being a desirable physical property of the quartz plates but does not teach how such a property is to be imparted thereto. Nor does he teach damping by employing an energy absorbing member attached to the plates. The Williams patent for depth sounding refers only to damping of electric oscillations and shows no means for accomplishing this result. Firestone teaches the means to produce voltage trains containing either a plurality of oscillations or as little as one-half a single oscillation. This provides a most effective means of damping. Defendants’ contention that Verman, et al. publication of 1934 discloses the electronic system used by Firestone, ignores the fact that the application of Firestone’s system is to the measurement and inspection of metal parts while Yerman deals with a system designed for “Recording the Retardation and intensities of echoes from the Ionosphere.” The device described in Verman does not differ significantly from the file wrapper reference of the Hart patent 1979225. Defendants also contend that Firestone does not teach the desirability of a short time constant but his disclosure that the amplifier should have a uniform response from 1,000 to 10,000,000 cycles per second is the equivalent of such teaching. The disclosure of a patent is presumed to be sufficient from the allowance and issuance of the patent. Holstensson v. Webcor, Inc., D.C., 150 F.Supp. 441. I find no inadequacy of disclosure sufficient to overcome that presumption. Alleged Anticipation of Claims 2, 3, 10 and 11 by (a) Publication of Verman et al; (b) Stocks and Rust Publication ; and (c) Sokolov Publication (a) As indicated above, the Verman publication relates to the location of ionized layers in the upper atmosphere by the application of the pulse echo method to pulses of electro-magnetic waves. The field of research in which the instrument discussed in Verman is employed is alone sufficient to distinguish that reference from the Firestone invention. This distinction is further illustrated by the substitution in Firestone’s invention of an electro-mechanical transducer for the antenna of Verman and the propagation of much shorter train waves. The contention of the defendants that Verman is distinguishable from the file wrapper reference of Hart because the latter shows a circular or rotating sweep is not well founded. Hart has a linear sweep. The Verman publication deals with the non-analogous art of radio and radar and it is clear that the above claims of Patent No. 1 are not anticipated by that reference. (b) The Stocks and Rust publication is a translation of an article in the German language which was published in 1935. That publication reports the results of echo soundings taken in the ocean and in the Harbor of Kiel where in some regions multiple echoes were observed, and the author suggests that these multiple echoes represent successive reflections from the bottom of the bay and from successive layers of ooze and mud. Defendants contend that ooze, mud and clay are solids but manifestly they are not the equivalents of the bounded parts referred to in the Firestone patent. Although counsel for defendants assert that the reference shows the penetration of rock at the bottom of the ocean, defendants’ expert witness, Fishleigh, stated : “I don’t find any indication of going into the rock.” While defendants place considerable emphasis on this translation as an anticipation of Patent No. 1, it seems clearly to be outside the scope of the prior art. It contains no teaching of the measurement, exploration or inspection of solid parts. The results of the tests described therein lead to few, if any, definitive findings. The authors refer to their surmises, assumptions and hopes and the need for further investigation to determine the speed of sound in mud. Expressions dealing with surmises and hopes appear on pages 3, 7 and 9 of the publication. This publication cannot be regarded as anticipating Firestone Patent No. 2280226. (c) The Sokolov reference is a translation of a Russian article published in 1935 on the subject “Ultrasonic method of determining internal flaws in metal parts.” The author is S. Y. Sokolov to whom Russian Patent No. 48894 was issued about 1936. On June 27, 1939 U.S. Patent No. 2164125, covering “Means for indicating flaws in materials,” was issued to S. Sokoloff on an application filed August 21, 1937. The U. S. Patent was a file wrapper reference against Firestone’s application for his No. 1 patent. The Russian patent is cited by defendants but it is not contended seriously that such reference constitutes an anticipation. The defendants, however, rely heavily upon the Russian publication of 1935. It is fair to say that of the hundreds of exhibits in the record, this reference has received the most elaborate treatment in the evidence and in the briefs of counsel. After a careful study of the evidence and arguments of counsel, I am of the opinion that Sokolov’s teaching differs from that of Firestone Patent No. 1 in many respects, including the following: 1. Firestone teaches that the trains of waves propagated into a work piece must be of shorter duration than the time intervals separating them in order that the reflected echoes may be received prior to the propagation of a subsequent train of waves. Sokolov teaches the propagation of successive groups of waves spaced by intervals of time equal to their own length. When the Sokolov transmitter is operating, the receiver is turned off and, conversely, when the receiver operates, the transmitter does not function. Thus, in Sokolov, energy is fed into the work piece half the time and this results in the delayed arrival of reflections at the receiver when it is turned off and produces the unfavorable effect of multiple reverberations. Defendants contend that plaintiffs do no more than merely emphasize this undesirable feature of the Sokolov device. However, Sokolov himself takes a more serious view of the matter, saying: “However, although the above methods permit the detection of heterogeneities in metals by the observation of maximal or minimal signals of the receiver, it is manifest that the unfavorable effect of multiple reflections of ultrasonic vibrations from the faces of the tested piece is not eliminated in the described methods. We need a somewhat different arrangement.” Sokolov, however, makes no provision for the observation of such “maximal or minimal signals” except by noting their different degrees of intensity. 2. The alternate method of flaw detection suggested by Sokolov depends upon the observation of the increase in the path followed by sound waves in passing around a flaw, when a flaw is present as compared to the length of the path of sound waves between the points of transmission and reception when no flaw is present. In marked contrast, Firestone teaches the measurement of the time required for sound waves to reach a flaw and be reflected directly therefrom to the receiver. The apparatus discussed by Sokolov is for flaw detection by the accoustieal shadow method, which is similar to the method described in the file wrapper reference of the Sokoloff United States patent, which does not provide for the measurement of time required for sound waves to reach a flaw and be reflected back. 3. The Sokolov publication provides no instrumentation for the presentation of signals from which accurate findings can be made in respect of the round trip travel time of sound waves through a work piece and their return to the receiver and the time of travel to a flaw and back again. Firestone, however, teaches the use of a cathode ray oscilloscope on which such a presentation is made. In an effort to supply the deficiency in Sokolov, the defendants’ expert, Fishleigh, produced a chart showing the system discussed by Sokolov with the addition of a cathode ray oscilloscope which he testified was an obvious improvement suggested by the reference. The testimony of Fishleigh in relation to the chart was given by him in surrebuttal. Earlier in the trial, Fishleigh admitted there was no suggestion in Sokolov that the signal output of the receiver be applied to an oscilloscope. In the Sokolov publication the author made reference to a cathode “oscillograph” in connection with his discussion of the phase difference between the generator and the receiver, stating that “a cathode oscillograph will be used for a convenient adjustment of the required phase.” Thus it appears that Sokolov intended to use an oscilloscope for a purpose other than that suggested by Fishleigh. The effect of Fishleigh’s testimony, however, is to demonstrate the need of an addition of an oscilloscope and a linear sweep to the Sokolov device. Such a necessary modification of Sokolov disqualifies it as an anticipation. In Topliff v. Topliff, 145 U.S. 156, 12 S.Ct. 825, 828, 36 L.Ed. 658, the Supreme Court laid down the rule that: “It is not sufficient, in order to constitute an anticipation of a pats ented invention, that the device relied upon might, by modification, be made to accomplish the function performed by that invention, if it were not designed by its maker, nor adapted, nor actually used for the performance of such function.” Moreover, it appears that other and substantial modifications of Sokolov not suggested in Fishleigh would be necessary to make that reference conform in structure, purpose and function with the teachings of Firestone. In Cold Metal Process Co. v. Carnegie-Illinois Steel Corp., 3 Cir., 108 F.2d 322, 336, it was held: “A prior device, in order to anticipate, * * * ‘must have been complete, and capable of producing the result sought to be accomplished; and this must be shown by the defendant.’ ” Furthermore, Sokolov, like Stocks and Rust, is a foreign reference and is effective only for what it clearly teaches and not for what may be made out of it. The Borg-Warner Corp. v. Mall Tool Co., 7 Cir., 220 F.2d 803. In Baldwin-Southwark Corp. v. Coe, 76 U.S.App.D.C. 412, 133 F.2d 359, it was held that, where a foreign publication is used as a reference one may not read into it any information which it does not afford on its face. Firestone’s Patent No. 1 is not anticipated by Sokolov. Alleged Anticipation of Claim No. 4, Patent No. 1 Claim No. 4 is more detailed than the other claims of Patent No. 1, and includes inter alia “an oscilloscope whose spot is deflected in one direction by said sweep circuit and is deflected in a different direction by the voltage output from said receiving transducer.” In support of their contention that Claim No. 4 is anticipated, defendants again refer to Sokolov, Verman and Stocks and Rust which are readily distinguishable but their principal reliance is upon Smith Patent No. 2143035. The Smith patent corresponds in significant respects to the file wrapper references of Hart and Langevin in effecting the synchronization of the operation of the transducer and the sweep of a cathode ray tube by means of mechanically operated switches. Such a method of synchronization is incapable of measuring accurately the short time intervals required by the operation of the flaw detecting apparatus invented by Firestone. The British patents cited by defendants are not materially different from the file wrapper references of Hart and McSpadden. The Smith-patent relates only to a “cathode ray oscilloscope” and does not disclose the medium in which the distance measurements are to be made. Smith shows no electronic means for synchronizing the sweep and transmission of the wave trains, and, like other prior art cited by defendants, Smith does not disclose the purpose, means and mechanism for accomplishing the end of the patent in suit and it is restricted to the accomplishment of a substantially limited and different purpose and cannot be regarded as an anticipation. Gordon Form Lathe Co. v. Walcott Machine Co., 6 Cir., 1929, 32 F.2d 55. Before closing the discussion of the validity of Patent No. 1, brief reference ought to be made to the numerous evidentiary facts that strengthen the statutory presumption of validity. That Firestone was the first to invent an apparatus capable of inspecting solid parts for flaws by the timing of echoes therefrom and measuring such parts by the timing of echoes from the opposite side of a part is beyond question. Witness after witness for the defendants attested to the priority and highly meritorious performance of the devices manufactured under the Firestone patents. The Firestone invention was described in most laudatory terms in respected scientific publications and unquestionably it filled a long felt need. Dr. Firestone’s achievement may be viewed in its true light by comparing it with the unsuccessful efforts of others, notably the Research staff of The General Electric Company. On February 10, 1943 W. D. Coolidge, Vice President and Director of Research of The General Electric Company, wrote a letter to Dr. Firestone in which he stated that he had just learned of Firestone’s success in developing “a supersonic method for the detection of flaws.” Coolidge also expressed a desire “to have one of our men visit you and learn about the potentialities of this method as well .as the possibility of our acquiring such a piece of equipment.” A significant paragraph of the letter reads: “Stimulated by a Russian publication in this field several years ago we had a try at this method but without getting results of practical value.” Whether the Russian publication referred to in the letter was the Sokolov publication of 1935 or one of his other articles which are exhibits in the record of this case is of relatively minor importance. 'The significant fact is that the highly skilled and superbly equipped staff of engineers and scientists in the Research Department of The General Electric Company, with knowledge of the prior art of a Russian publication, were unable to accomplish the results achieved by Firestone. Defendants attack the validity of fhe patent on the ground that all of the elements of the patent are old. It has long been settled law that a combination .of old elements achieving a new and useful result is a patentable invention. Walker on Patents, Deller Ed., Vol. 1, 1957 Supp., p. 215. Defendants also advance the argument that a mere change in the degree of accuracy of measurement is not invention particularly where all components contributing to such change are commercially available. In support of this claim defendants cite and rely upon Paramount Publix Corp. v. American Tri-Ergon Corp., 294 U.S. 464, 55 S.Ct. 449, 79 L.Ed. 997; Altoona Publix Theatres, Inc. v. American Tri-Ergon Corp., 294 U.S. 477, 55 S.Ct. 455, 79 L.Ed. 1005; Suczek v. General Motors Corp., 6 Cir., 132 F.2d 371; Buffalo-Springfield Roller Co. v. Galion Iron Works, 6 Cir., 215 F.2d 686; Lempco Products, Inc. v. Simmons, 6 Cir., 140 F.2d 58. All of the cited cases are readily distinguishable on their facts. They enunciate no principle that requires a holding that a device for testing solid parts is unpatentable over depth sounding devices where, as here, the patented device operates by measurement of time intervals infinitely shorter than those measured by the depth sounding devices and where depth sounding devices were considered by the Patent Office in granting the patent. Validity of Claims 19 and 32 of Patent 2398701 (Patent No. 2) Patent No. 2 relates to improvements of Patent No. 1 in the following respects: 1. Damping of the transducer. 2. The amplification of the voltage produced by the reflections by the use of a heterodyne amplifier, the intermediate frequency of which is higher than the frequency of the oscillations in the ultrasonic wave trains. 3. The use of improved means for the application of a train of voltage oscillations to the sending crystal. In support of their contention that Claims 19 and 32, which relate to the damping feature of the patent, are invalid, defendants again rely on the Russian publication of Sokolov as an anticipation. While Sokolov refers to the need of a “damping decrement,” he does not teach how the damping is to be accomplished and, as hereinbefore noted, a foreign reference is good only for what it clearly teaches. Borg-Warner Corp. v. Mall Tool Co., supra. Defendants also refer to the “inertia member” of the Hayes patent, No. 2424030. However, this is a tuning member and it has not been shown that it was also designed for use as a means of damping. Defendants’ chief reliance is upon the Bond-Mason patent, No. 2427348. That patent issued September 16,1947 on an application filed August 19, 1941. The Firestone application for Patent No. 2 was filed June 29, 1942 and the patent awarded to Firestone April 16, 1946, — about a year and a half before the Bond and Mason patent issued. Dr. Firestone admitted that “Bond and Mason have indeed utilized the back side of a crystal plate for the application of a damping member.” However, Dr. Firestone also testified that he completed his invention before the filing date of the Bond and Mason application, and supported such testimony by notebook entries of January 10, 1941 and February 4, 1941 and a letter to Edward Eaton dated January 15, 1941. These exhibits corroborate Dr. Firestone’s testimony and are sufficient to antedate the reference. Armstrong v. De Forest Radio Tel. & Tel. Co., 2 Cir., 280 F. 584. However, defendants contend that Firestone’s failure to apply for a patent until June 1942 shows that the tests of early 1941 were no more than abandoned experiments. In support of this contention defendants cite and rely upon Electro Metallurgical Co. v. Krupp Nirosta Co., D.C., 33 F.Supp. 324, 328, wherein it was held that the delay of the patentees in that case in filing their application “proves that an alleged earlier reduction to practice was * * * nothing more than an unsatisfactory or abandoned experiment.” The cited case is not in point as shown by the following excerpts from page 328 of the opinion: “There can not be a reduction to practice unless the inventor knows what he is doing. * * * “If Becket and Franks are to prevail as prior inventors they must show, either that they had successfully reduced their invention to practice before the filing date of Schafmeister’s German application, i. e., July 21, 1930, or that they had conceived the invention before that date, and thereafter coupled their conception to reduction to practice by diligent efforts. In fact, they did not know what they were doing.” The evidence demonstrates that in January and February of 1941 Dr. Firestone did know precisely what he was doing and that his tests were successful. In the tests of January-February 1941 wax was used as the damping means, whereas in the application for the patent the damping means were described as “consisting usually in cementing the back of the crystal to a block of Bakelite, lead or other material which absorbs high frequency waves instead of transmitting them.” However, this is not a fatal variance. The statute requires that the inventor set forth the best method contemplated by him at the time of his application but this does not preclude him from showing an earlier completion of his invention by the use of another material performing the same function. The claims in question disclose a damping means which “absorb high frequency waves instead of transmitting them.” Wax is such a material. The Bond and Mason patent came after Firestone and although his application was later than that of the cited reference, Firestone’s reduction to practice was earlier. Claims 19 and 32 are not anticipated. Validity of Claims 16, 25, 29 of Patent No. 2398701 (Patent No. 2) Claim 16, which is representative of the three claims mentioned above, reads: “16. In a device for the inspection or measurement of a part by means of supersonic vibration waves having means for producing a supersonic voltage train and an electromechanical transducer actuated by said voltage train producing means and having its sensitive area in effective contact with said part so as to radiate vibration wave trains into said part and generate voltage trains in response to wave trains reflected within said part; a hetero-dyne amplifier actuated by said transducer and having an intermediate frequency higher than the frequency of the alternations produced by said voltage train producing means and means actuated by said amplifier for indicating the time intervals between the voltage trains.” In support of their contention that the three claims in question are invalid, the defendants rely chiefly upon Harrison patent No. 2433361, issued December 30, 1947 on an application filed June 20,1940, and Weisman Patent No. 2491540, issued December 20, 1949 on application filed December 31, 1940. While there is a similarity in the apparatus of each of the references and that of Claims 16, 25 and 29, and each reference provides for a heterodyne amplifier whose intermediate frequency is higher than the signal frequency, both references disclose a device for use in the different art of depth sounding and neither reference discloses a device for the measurement of a part or for the detection of flaws in metal parts. Harrison shows a transmission that is discontinuous but his device also provides for wave signal impulses that vary continuously in frequency between the predetermined limits preferably in the supersonic range. The patent provides further: “The fluctuation frequency, that is the number of times per second that a transmitted signal completes a cycle of frequency change between the said limits, is preferably of an audio frequency high enough to make possible a considerable number of complete frequency fluctuation cycles during the time length of the transmitted impulse.” The variation of frequency in the high audio range indicates that each outgoing pulse in Harrison is incomparably longer in time than the “extremely short time duration” taught by Firestone. The Harrison device is therefore not adaptable to the inspection of flaws located close to the surface of a metal part, as taught by Firestone. Harrison’s device is an improvement on other similar devices patented by him and is designed inter alia to reduce the reverberations from noises, some of which are produced “by the motion of the ship through water, by the action of the ship’s propeller or by sounds conducted to the water through the ship’s skin.” As stated in Patent No. 2, the purpose of a heterodyne amplifier whose intermediate frequency is greater than the signal frequency is to provide an amplifier that can recover its sensitivity within approximately a millionth of a second after the initial wave train is sent out. Defendants contend that by his reference to the “blocking” of an amplifier Firestone merely describes in a new way the characteristics of a wide band pass or short time constants which increased the ability of the receiver to distinguish pulses separated by short intervals of time. This contention fails to recognize the true meaning of the term “blocking” and the object accomplished by the use in the Firestone patent of a heterodyne amplifier whose intermediate frequency is higher than the signal frequency. In an amplifier having a sufficiently wide band width pulses closely following each other will get through without overlapping. The “blocking” to which Firestone refers is the paralysis which overtakes an amplifier irrespective of its band width when the amplifier is overloaded by a signal of too high amplitude. The powerful thrust of the input signal of Firestone's device resulted in paraylsis or loss of sensitivity of the amplifier. Firestone was therefore confronted with the problem of providing an amplifier which would recover its sensitivity within approximately one millionth of a second so that it would be sensitive to the feeble train waves reflected back to the crystal from flaws distant only a fraction of an inch from the sending point. Firestone solved this problem by the use of the heterodyne amplifier whose intermediate frequency was greater than the signal frequency. The problem of “blocking” or receiver recovery did not arise in the operation of Harrison’s depth sounding device with its long pulse substantially continuous wave system. Nor can it fairly be said on the authority of General Electric Co. v. Jewel Incandescent Lamp Co., 326 U.S. 242, 66 S.Ct. 81, 90 L.Ed. 43, that Firestone’s use of an old device of a heterodyne amplifier was not invention. Firestone did more than merely recognize a feature or advantage of a heterodyne amplifier as used in the depth sounding art. He used the heterodyne amplifier in the different art of non-destructive testing by the new technique of the ultrasonic pulse echo method to effect the novel and useful result of enabling the receiver speedily to recover its sensitivity and reflect the echoes from flaws close to the surface of the piece under inspection. Thus, by the use of imagination and inventive skill, Firestone adapted an old device to a new use in a different art and achieved an unobvious and useful result. The principle applicable here was well stated in Potts v. Creager, 155 U.S. 597, 607, 15 S.Ct. 194, 198, 39 L.Ed. 275, where it was said: “Indeed, it often requires as an acute perception of the relation between cause and effect, and as much of the peculiar intuitive genius which is the characteristic of great inventors, to grasp the idea that a device used in one art may be made available in another, as would be necessary to create the device de novo.” The Weisman patent, like Harrison, discloses a depth sounding device and an echo ranging system but it discloses no means for keying the operation of the transmission to provide for the intermittent transmission of pulses. Apparently Weisman’s transmitter operates continuously and in this respect differs from that of Firestone. No satisfactory showing has been made that Weisman’s device is adaptable to the inspection of flaws close to the surface of a solid part or that Weisman was in any way concerned with the problems arising in connection with the use of a device to accomplish that purpose. There is nothing in the disclosures of the depth sounding devices of Harrison or Weisman that would teach a workman skilled in the art of nondestructive testing the solution of the problem solved by Firestone. Neither of the references cited by defendants anticipate the claims in question. Defendants’ argument that Claims 16, 25, 29 of Patent No. 2 were anticipated by Firestone’s Patent No. 1 is not persuasive. Firestone was the inventor of Patent No. 1 and also invented meritorious improvements of his original device. In Eibel Process Co. v. Minnesota & Ontario Paper Co., 261 U.S. 45, at page 63, 43 S.Ct. 322, at page 328, 67 L.Ed. 523, the Supreme Court, speaking through Chief Justice Taft, held that a meritorious improvement was entitled to liberal treatment. While the “improver” in that case was not the inventor of the original machine, the following statement of the court is nevertheless pertinent here: “Indeed, when one notes the crude working of machines of famous pioneer inventions and discoveries, and compares them with the modern machines and processes exemplifying the principle of the pioneer discovery, one hesitates in the division of credit between the original inventor and the improvers, and certainly finds no reason to withhold from the really meritorious improver, the application of the rule ‘ut res magis valet quam pereat,’ which has been sustained in so many cases in this court. (Citing cases.)” The claims here under discussion are not anticipated by Firestone’s Patent No. 2280226. Validity of Claims 20 and 26 of Patent No. 2. These claims are for a combination of damping means and the heterodyne amplifier. As shown by the evidence, the incorporation of these elements in the apparatus of Patent No. 2 makes possible the discovery of flaws located close to the surface of the part under inspection. Defendants contend that the combination is an old one and they restate their arguments that both elements were anticipated by the prior art. It is unnecessary to repeat the findings hereinabove made as to the alleged anticipation of the damping means and the heterodyne amplifier considered as separate elements. Defendants’ argument that the combination is an old one is not supported by the references cited by them. None of such references shows the combination. Nor can the inclusion of both elements in the device be considered as a mere aggregation. The proper test to be applied was laid down by Judge Learned Hand in Sachs v. Hartford Electric Supply Co., 2 Cir., 47 F.2d 743, 748, where inter alia he said: “ * * * The co-operation of the means necessary to create an invention is to be measured by the purpose to be fulfilled, not by the interaction of the parts. Each factor must indeed be a condition to that result, but the whole may be a mere assemblage; the co-operation between them all may be no more than their necessary presence in a unit which shall answer a single purpose.” I hold that combination Claims 20 and 26 are valid. Validity of Claim No. 7 of Patent No. 2. Claim No. 7 reads: “A voltage train generator comprising a condenser, means for charging said condenser, a grid controlled discharge tube having its plate connected to one terminal of said condenser and its cathode connected through a resistor to the other terminal of said condenser, an oscillatory circuit connected in parallel with said resistor, a pair of output terminals connected to said oscillatory circuit, and means for periodically discharging said condenser through said tube.” Among the prior art cited by defendants and not cited by the Patent Office are the Langevin Patent No. 1858931 and an article in The Hydrographic Review of 1934, the Newhouse patent No. 2083344, an article by Everett in the standard textbook “Communication Engineering” published in 1937, and the Gunn Patent No. 2461543. Both Langevin and the Hydrographic Review disclose an oscillatory circuit similar to that in Claim No. 7 but both such references use a spark gap or spark break. Defendants claim that these elements of the references are the equivalent of the grid controlled discharge tube of Claim No. 7. However, the evidence shows that the uniformity of repetitive action of a grid controlled gas tube which is essential to the effective operation of the apparatus of Patent No. 2 cannot be obtained by the erratic action of a spark break. Nor is the resistor disclosed in Patent No. 2 found in Langevin or the Hydrographic Review. Nevertheless it was shown by the uncontradicted testimony of defendants’ expert witness that the Newhouse patent discloses a grid controlled gas tube and it would be an obvious expedient to combine such a grid controlled tube with the oscillatory circuits of Langevin or the Hydrographic Review. Moreover, Firestone testified that the Gunn patent discloses a grid controlled gas tube connected to one terminal of the condenser with its cathode connected through a resistor to the other terminal of the condenser as shown in Claim No. 7. Obviously these elements in Gunn, which perform the same function as the spark break and associated elements of Langevin and Hydro-graphic Review, could be substituted therefor. It is also obvious that the oscillatory circuits of Langevin and Hydro-graphic Review could be used in Gunn. It appea