delivered the opinion of the court:
This case is before us on the sole question of the validity of claim 1 of plaintiff’s patent, which plaintiff alleges the defendant infringed. The question of infringement, however, is not before us at this time. Claim 1 reads:
A low compression motor fuel, such as gasoline or kerosene, containing a compound belonging to the mesitylene group.
As explained in the specifications:
This invention relates to the suppression of a fuel knock in a motor when a mixture of a low compression fuel, such as gasoline or kerosene, and air is burned under a relatively high compression.
A knock in an engine is caused by an uneven burning of the fuel and by its too rapid combustion. It is accompanied by overheating, increased vibration, and loss of power.
On motion of the parties, the court directed the Commissioner to report not only his findings of fact, but also his recommendation for a conclusion of law. The briefs before us are directed to the Commissioner’s memorandum in support of his recommendation for the conclusion of law to be entered; the facts are not in dispute.
It is said that petroleum, wherever found, with only one or two exceptions, contains mesitylene and that, therefore, plaintiff’s claim of “a low compression motor fuel, such as gasoline or kerosene, containing a compound belonging to *429the mesitylene group,” claims nothing more than what already existed. However, it seems to us that the claim of the patent must of necessity be construed as meaning a motor fuel to which is added an amount of mesitylene in addition to that found in the gasoline produced from petroleum, both by distillation and by cracking. In short, it means adding more mesitylene than can be obtained from the gasoline itself.
This is necessarily true, because if not so construed, manifestly nothing had been invented and no patent would have issued on it. The inventor discovered the fact that mesity-lene prevented knocking; a knock occurred in low compression gasoline when subjected to high compression and, therefore, the inventor said, add more mesitylene to the gasoline and the knock will be prevented.
A reference to the specifications demonstrates that this is what the claim meant. But before we quote the specifications we should notice the Commissioner’s statement that the specifications may not be looked to if the claim is unambiguous, and his further statement that the claim is not ambiguous. We must disagree with the Commissioner. The question is, did the inventor mean to add to gasoline an amount of mesitylene which was not naturally present ? The claim does not say specifically whether he does or not, although, as we said above, we think this must be inferred; but since there is a doubt about this, the claim is ambiguous and we may turn to the specifications to resolve the doubt.
In the second paragraph of the specifications he says:
I have found that compounds of the mesitylene group, which includes the substance mesitylene, its amino-compounds and derivatives of the amino-compounds, suppress this fuel knock when the fuel mixture is burned in the presence of one of these compounds. * * * [Italics ours.]
This would indicate an addition of mesitylene that was not found in the gasoline in its natural state. In the next paragraph he says:
In a commercial method of utilizing- the invention one or more of these mesitylenes is admixed with or dissolved iii the liquid fuel, * * *. [Italics ours.]
*430This, of course, means the addition of something to the gasoline.
The next paragraph makes this all the more plain:
The same result may be obtained by feeding one of the mesitylenes into the intake of the engine as by atomizing it therein or by feeding it into the combustion chamber of the engine prior to ignition.
When we look to the specifications, there seems to be no doubt but that the inventor had in mind the addition to the motor fuel of mesitylenes which were not naturally found in that fuel.
It is also said that plaintiff’s patent is anticipated by the Taber and Essex patent. The Taber and Essex patent discloses a motor fuel consisting of gasoline modified by an additive consisting of solvent naphtha, comprised principally of xylenes, together with ethyl benzol, mesitylene and analogous benzol derivatives. Since mesitylene was present in the things which the Taber and Essex patent specified should be added to the gasoline, plaintiff’s patent is said to be anticipated by it. We do not think this is correct.
The Taber and Essex patent says that the solvent naphtha to be added to the gasoline should be comprised “principally of xylenes,” and then it adds: “together with ethyl benzol, mesitylene and analogous benzol derivatives.” The principal thing which the Taber and Essex patent said should be added to the gasoline was a naphtha comprised principally of xylenes. The ethyl benzol, the mesitylene and the analogous benzol derivatives were merely “also-rans.” The main horses in the race were xylenes; the ethyl benzol, mesitylene, and analogous benzol derivatives “also ran.” The star of the cast was the xylene; the bit players were ethyl benzol, mesitylene, and analogous benzol derivatives. Plaintiff said nothing about the addition of xylenes and the rest, but only of mesitylene.
It is true that xylene and mesitylene are closely related; but they are different, as the Taber and Essex patent recognized, by mentioning principally xylene, but also mentioning, secondarily, mesitylene. If they were the same, both would not have been mentioned. The chemical formula for *431xylene reads: “C6H4(CH8)2.” The formula for mesitylene is“C6H3(CH3)3.”
Since Taber and Essex centered their attention on xylenes, and only mentioned mesitylene incidentally, whereas plaintiff centered his entire attention on mesitylene, it does not seem to us that the Taber and Essex patent anticipated plaintiff’s patent.
It is also suggested that plaintiff’s claim is fatally vague and indefinite, in that it does not specify to those skilled in the art the proportion of mesitylene to be used. We think this suggestion is well answered by plaintiff’s brief, on page 16. It is there stated:
The patentee’s discovery is not concerned with proportions. Like any other antiknock additive, the amount used is determined by the result desired. If it is desired to render a fuel suitable for an engine having a 6 to 1 compression ratio effective in an engine having an 8 to 1 compression ratio, a greater amount will be added than if it is desired to make the fuel suitable for an engine having a 7 to 1 compression ratio. * * *
It is like sweetening one’s tea or coffee: you do it according to taste. Some people put one lump of sugar in their coffee; a person has been known to put as many as six. The result desired determines the amount of sugar; the result desired determines the amount of mesitylene.
In the specifications of the patent plantiff says:
By way of example, I may dissolve twenty grams of the diamino-mesitylene in twenty cubic centimeters of ethyl alcohol and mix this solution into one gallon of gasoline. This proportion quantity of anti-knock substance will suppress a knock in present day automobile engines and generally will permit increasing the compression pressure of the engine about twenty pounds.
Plaintiff states how much mesitylene must be added to suppress a knock “in present day automobile engines,” but evidently if the compression in such an engine goes higher, more mesitylene must be added; the higher the compression, the more mesitylene to be added.
It seems to us that the claim is definite enough, when read in connection with the specifications. It would be im*432possible to specify the exact amount unless the result desired was known, and the character of the gasoline used was known, because the mesitylene content of gasoline varies from field to field, as the findings show. Having been told that the addition of mesitylene would prevent a knock, any one skilled in the art by a little experimentation could readily determine the amount to be added.
We are of the opinion that the Patent Office was correct in issuing a patent (No. 1,713,589) to plaintiff covering his discovery that mesitylene in addition to that naturally found in gasoline would prevent a knock.
The case will be remanded to a commissioner for further proceedings not inconsistent with this opinion.
It is so ordered.
Laramore, Judge; MaddeN, Judge; and JoNes, OMef Judge, concur. Littleton, Judge, dissents.FINDINGS OF FACT
The court, having considered the evidence, the report of Commissioner Hayner H. Gordon, and the briefs and argument of counsel, makes findings of fact as follows:
1. This is a suit, filed June 25, 1948, for alleged infringement of claim 1 of United States patent No. 1,713,589, in evidence as joint exhibit A, entitled “Low-Compression Fuel”, and issued May 21,1929, on an application filed September 17,1925, by the plaintiff Bereslavsky. The plaintiff, at the time of filing the present suit, and for six years prior thereto, was, and still is, a citizen of the United States of America, and the owner of the entire right, title and interest in and to these letters patent, and to all rights of recovery for infringement thereof.
2. The patent in suit relates to an alleged improvement in what the patent terms “a low compression motor fuel, such as gasoline or kerosene”, aimed at reducing fuel knock when a mixture of such low compression fuel and air “is, burned under a relatively high compression.” There is no evidence that the patentee either conceived or reduced to practice the subject matter of the patent in suit at any date earlier than the date of filing of his application, September 17,1925.
*4333. To obtain combustion of the fuel in a conventional so-called four-cycle internal combustion engine utilizing spark-plug ignition, the fuel is vaporized and mixed with air in a device known as a carburetor. On the downward stroke of a piston this mixture is drawn into the engine cylinder. On the return or upward stroke of the piston this mixture is then compressed into the upper portion of the cylinder. As the piston reaches its approximate top position in the cylinder, the compressed mixture is then ignited by an electric spark plug, and burns, producing heat and increased pressure within the combustion chamber, pushing the piston out, thus applying power to the crankshaft. On the next upward stroke of the piston an exhaust valve is opened and the burnt gases are discharged.
4. The term “compression ratio” is used in the art to define the ratio in the volumetric capacity of the engine cylinder when the piston is at the outer end of its travel, as compared to the decreased volumetric capacity existing in the cylinder when the piston is at the inner end of its travel, i. e., the ratio between the total volumetric capacity of the cylinder as compared to the compression space in which the fuel mixture is compressed prior to ignition.
It was known prior to plaintiff’s filing date that an internal combustion engine that had a high compression ratio is more efficient than one with a low compression ratio, other things being the same. It was also known that one factor limiting the degree of compression that could be employed in a spark-ignition engine was the so-called “knocking” characteristic of the fuel, a phenomenon familiar to all automobile drivers.
5. Knocking is a form of too rapid combustion, resulting in rapid energy release or detonation, usually (but not always) manifested by an audible knock in the engine, and is also evidenced by overheating, increased vibration, loss of power, increase in minimum speed before stalling, and a reduction in gasoline mileage per gallon. Modern research indicates that knocking is a form of spontaneous ignition which takes place ahead of the orderly progressing flame front, usually at some section of the combustion chamber wall. Knocking also increases the wear and tear on the engine and car generally.
*4346. Because of the brevity of the specification of the patent in suit, it is set forth in its entirety as follows:
This invention relates to the suppression of a fuel knock in a motor when a mixture of a low compression fuel, such as gasoline or kerosene, and air is burned under a relatively high compression.
I have found that compounds of the mesitylene group, which includes the substance mesitylene, its amino-compounds and derivatives of the amino-compounds, suppress this fuel knock when the fuel mixture is burned in the presence of one of these compounds. These compounds include mesidine, diamino-mesitylene, triamino-mesitylene or their corresponding methyl and ethyl compounds.
In a commercial method of utilizing the invention, one or more of these mesity lenes is admixed with or dissolved in the liquid fuel, alcohol benzol, or some other blending agent, being employed, if desired, to effect a homogeneous admixture.
The same result may be obtained by feeding one of the mesity] enes into the intake of the engine as by atomizing it therein or by feeding it into the combustion chamber of the engine prior to ignition.
By way of example, I may dissolve twenty grams of the diamino-mesitylene in twenty cubic centimeters of ethyl alcohol and mix this solution into one gallon of gasoline. This proportion quantity of anti-knock substance will suppress a knock in present day automobile engines and generally will permit increasing the compression pressure of the engine about twenty pounds.
The effectiveness of the compounds of the mesitylene family as anti-knocks varies, and in general the compounds having the higher specific gravity are more effective quantitatively than the compounds having the lower specific gravity.
7. Claim 1 of the patent, the only claim in suit, is as follows:
1. A low compression motor fuel, such as gasoline or kerosene, containing a compound belonging to the mesitylene group.
8. No one of the materials, petroleum, coal tar, gasoline, or kerosene is a simple chemical compound. Each is a mixture of a great many compounds, principally hydrocarbons. The composition of petroleum varies from oil field to oil field, *435and the composition of gasolines and kerosenes made therefrom varies, depending, among other factors, on the field from which the petroleum comes, the particular process by which the gasoline or kerosene is made, and even on day-today operation of the same distillery, cracking, or blending plant. Similarly, the composition of coal tars varies from plant to plant as the raw materials and the processes to which they are submitted vary. Furthermore, the boiling range of a gasoline made for winter use will be different from that made for summer use. The former will contain a greater proportion of the lower boiling point compounds, or light “ends”, so as to give easier starting in cold weather.
Gasoline and kerosene differ physically in that kerosene has a starting boiling point higher than that of gasoline, and a higher end boiling point. The kerosene starting boiling point is lower than the gasoline end boiling point, so that there is a zone of temperature overlap between them. Within the zone of temperature overlap, both may contain the same compounds, but gasoline also contains compounds boiling below the starting boiling point of kerosene, and kerosene contains compounds boiling above the end boiling point of gasoline. Gasoline has no legally established or generally accepted fixed commercial standard of boiling range, but a boiling range of from 27-225° C. would be generally considered to embrace all gasolines. The boiling range of ordinary gasoline in 1925 was about 39-225° C. (100-437° F.). The end point of automobile gasoline was later reduced in some Government specifications to 211° C. (412° F.), and still later to about 205° C. (4.00° F.). Kerosene likewise has no legal standard, but a boiling range of from 175°-325° C. (347°-617° F.) would include most kerosenes. Both gasoline and kerosene had been used prior to the plaintiff’s earliest claimed date for spark-ignition internal combustion engine fuels.
9. In general, the first treatment of a crude petroleum oil at the refinery consists of a distillation to separate the different gross fractions. The gases methane to butane come off first. Then petroleum ether (boiling range 20° to 60° C.) is distilled off. This is followed by ligroin (60°-100° C.), gasoline (40°-205° O.), kerosene (175°-325° C.), gas oil (above *436275° C.) and, finally, lubricating oil. The residue may be either asphalt or petroleum coke, depending upon the nature of the petroleum.
10. Prior to the plaintiff’s earliest claimed date, it was known that the yield of gasoline from petroleum could be increased by so-called cracking. The earliest form of cracking was the application of heat and pressure to petroleum heavy distillate. This caused the complex molecules to “crack” or break down into simpler ones, giving a greater yield of lower boiling point compounds than could be obtained in a simple distillation process. Later, as the art of cracking developed, it was found that the desired yield could be still greater increased by the use of catalysts, substances well known to chemists, which have the property of altering the nature and velocity of chemical reactions. The precise chemistry of cracking and the reactions which occur in it are not completely understood even now. The quantity of gasoline obtainable from crude petroleum by simple distillation, without the use of cracking, would be quite inadequate to supply present demands.
11. Mesitylene is defined in the 1913 edition of Webster’s Dictionary (joint exhibit D-27) as follows:
A colorless oily hydrocarbon, C6H3 (CH3)3, occurring in coal tar and petroleum, and also prepared artificially, as by distilling acetone with sulphuric acid. It is the symmetrical trimethyl derivative of benzene.
A research paper, Volume 39, November 1947, of the United States Department of Commerce (joint exhibit F) presents in table 3 the percentage by volume of mesitylene present in seven representative crude petroleums, as follows:
(A) Ponca, Oída_ 0.12
(B) East Texas_ 0. 09
(O) Bradford, Pa_ 0.17
(D) Greendale-Kawkawlin, Mich_ 0.05
(E) Winkler, Tex_ 0.05
(P) Midway, Oalif_ 0.05
(G) Conroe, Tex- 0. 36
This table also shows that the mesitylene content of the naphtha fraction (40-180° C.) of the same crude petroleums varies from 0.22 percent to 1.34 percent by volume of the *437naphtha fraction. The naphtha fraction (40-180° C.) is a close approximation to the gasoline fraction (40-205° C.).
In connection with this report of 1947, which is listed in paragraph 6 of the stipulation, the parties have agreed as follows:
There is no evidence to show, and no reason to believe, that the average composition of petroleum in the ground has changed between the earliest date of any of the references listed in paragraph 6 of this stipulation and the present, and analyses of samples of petroleum taken and made subsequent to that date may be considered to have the same force and effect that they would have if they had been taken and made at the present time, and vice versa.
Petroleum, Redwood, (1913) pp. 246, 247 (joint exhibit D-18) refers to the aromatic hydrocarbons of the benzene series found in petroleum from different fields, and lists a number of petroleums from different sources which contain mesitylene. This article also states that no mesitylene is found in the petroleum from Gemsah on the Red Sea.
Das Erdöl, Engler & Hofer, Vol. 1, pp. 356-368, and pp. 573, 577 (joint exhibit D-19) is an elaborate summary of the literature relative to the occurrence of aromatic hydrocarbons of the benzene series in petroleums from many localities. It also contains some discussion of the changes in composition resulting from cracking of heavy oils with the formation of aromatic compounds, including mesitylene.
12. The file wrapper and contents of the application that materialized into the patent in suit (joint exhibit B) show that the Patent Office cited but one reference. This was the French patent to Mascia No. 531,367 and its translation (joint exhibit C). This prior art patent relates to the addition to kerosenes, gasolines, and benzenes, of a mixture of organic products intended to augment their carburetting power and in consequence to diminish the consumption of fuel in internal combustion engines. The French patent stated that the additives were hydrocarbons of the aromatic series belonging to the family of xylenes C6H4 (CH3)2 and the family of the triphenyl methane group. The plaintiff, in reply to the rejection, pointed out in summarization that *438(1) tbe French patent was for better carburetion and not antiknock, (2) that it was a well known fact that xylene and mesitylene are compounds of two different independent chemical groups, and that each one is the head of its respective group; and (3) that the product suggested by the French patent is a powder whereas mesitylene is a liquid. The Patent Office allowed plaintiff’s claims in view of plaintiff’s argument.
13. United States patent to Taber and Essex No. 1,495,501 (joint exhibit D-7) was issued on May 27, 1924, which is prior to the plaintiff’s effective date, and is therefore prior art. This patent was not cited by the Patent Office during the prosecution of the Bereslavsky application which materialized into the patent in suit. This patent discloses and claims a motor fuel consisting of gasoline modified by adding a mesitylene-containing mixture thereto. The patent further states that the fuel may be from 70 parts of gasoline, with 30 parts of solvent naphtha added, to 10 parts of gasoline with 90 parts of solvent naphtha added. The solvent naphtha is stated in the Taber and Essex patent to consist principally of xylenes, together with ethyl benzol, mesitylene and analogous benzol derivatives.
The catalog of benefits derived from the use of this additive to gasoline recited in the patent, is that the fuel gives improved operation, including better fuel economy; materially increased flexibility; greater maximum power; more horsepower in climbing hills, and that it was found possible to run steadily on level stretches of road in high gear at a low speed of 1 mile an hour, whereas the best that could be done with gasoline was 3 miles an hour under the same conditions. It was also found possible to accelerate the automobile from 3 miles an hour to 25 miles an hour as compared to 3 miles an hour to 22 miles an hour in the same time interval when compared to the fuel without the additive; also, a very materially decreased speed due to throttling, as compared with gasoline and without the modification of the carburetor adjustment set for gasoline.
While this patent does not specifically use the term “antiknock”, all of these benefits are concomitant with decreased engine knock.
*43914. While the patent in suit states, by way of an example, 20 grams of diamino-mesitylene added to 1 gallon of gasoline, the patent is not limited to any specific proportionate mixture of mesitylene with gasoline, nor is the claim in suit in any way limited to any proportionate mixture.
CONCLUSION OF LAW
Upon the foregoing findings of fact, which are made a part of the judgment herein, the Court concludes as a matter of law that plaintiff’s patent No. 1,713,589 is valid.
The case is remanded to a commissioner for further proceedings not inconsistent with this opinion.