of the firm to which the letter had been sent. They conferred together shortly before their examination, and endeavored to fix the time at which it had been received. They knew, so far as they had not forgotten, every circumstance which might serve to bring to the memory of either of them the fact which they desired to recall, but neither of them was able to say more, when examined, than what he "presumed" or "should judge" upon the subject; and their testimony with respect to it is argumentatively based upon supposed presumptions, which, if allowable at all, would be for application by the court, and not by a witness. They are, however, not allowable at all. "There is no presumption of law that a letter directed and mailed to one at the place where he usually received his letters was received by him." Bank v. MeManigle, 69 Pa. St. 156; Kenney v. Altvater, 77 Pa. St. 38. From its postmark, the fact that a letter was mailed may be inferred; but by that, or other admissible evidence, the mailing, when material, must be proved. It will not be presumed from evidence that it had been written. So as to time of mailing. No presumption whatever arises from the date written in the letter; and in this case no evidence, direct or otherwise, of the actual time of posting, was offered. We have not, nor had the witnesses, anything upon which to legitimately base a calculation of the time at which this letter was received; but, even if the time of mailing had been conclusively shown, it still would not be permissible to accept the result of a calculation founded thereon, as determining the date of delivery. The date of a postmark upon a letter is not evidence that it was forwarded on that day. Bank v. Townsley, 102 Mass. 177. A fortiori the date of a letter is not; nor even, it would seem, direct proof of actual time of posting; and yet upon the date of this letter all proof of the time of its receipt is clearly dependent. It is, of course, quite possible that the fact is as the witnesses have supposed it to be, but the suppositions of witnesses are not proof. Nor may the court, in the absence of proof,-except that this letter bore a certain date, was at some time mailed, and was at some subsequent time received,-presume that it was received upon any particular day, or within any particular period. The claim of a February, 1887, date for the Klein has not been maintained.

Has a March, 1887, date for the Stockheim been shown? This depends upon the correct reading of an application filed March 2, 1887, on behalf of Stockheim, for a patent (No. 229,423) for an "improvement in filtering apparatus." Here we have no question of time to determine, but only whether the application referred to fully disclosed, as is claimed, the invention of the later patent in suit. Judge Gresham (Uhlmann v. Brewing Co., 41 Fed. Rep. 139) and the commissioner of patents (Zwietusch v. Stockheim, 53 O. G. 758) appear to have held that it did; and my own examination and consideration of the document itself have led me to the same conclusion. Dr. Henry Morton, an expert witness, has in this case distinctly and positively testified to the same effect, and the grounds assigned by him for his opinion and testimony are satisfactory to me. Nothing more need be said. The claim of a March 2, 1887, date for the Stockheim has been supported.

Upon all the evidence, I am of opinion that the defense of anticipation by the Klein invention, which the defendant uses, has not been established.

The remaining defenses involve construction of the patent; determination of its validity; the question of infringement.

1. The claims are as follows:

"(1) The process of filtering beer, consisting in drawing the beer to be filtered from the cask under a pressure exceeding atmospheric pressure, conducting the same to and through a filtering apparatus in which that pressure is maintained during the filtering operation, keeping the filtering apparatus full of beer, collecting and carrying off any air entering the filter along with the beer, and gas separating from the beer during the filtering operation, and discharging the filtered beer from the filter under pressure, substantially as hereinbefore set forth.

"(2) The described process of filtering and keeping beer, which consists in forcing the beer under a pressure exceeding atmospheric pressure from the store cask through a filtering apparatus, and thence to the keg, keeping said apparatus full of beer during the operation, and collecting and carrying off from the beer, during its passage from the store cask to the keg, air that may be mingled with the beer, and gas that may separate from the beer, substantially as and for the purposes hereinbefore set forth.

"(3) The process of filtering beer, consisting in drawing the beer from the cask under a pressure exceeding ordinary atmospheric pressure, forcing the beer under said pressure through a filter, maintaining that pressure in the filter during the filtering operation, and creating and maintaining a back pressure in the filter, so as to keep the filter full of beer, substantially as described.

"(4) The process of filtering beer, consisting in drawing the beer from the cask under a pressure exceeding ordinary atmospheric pressure, forcing the beer under said pressure through a filter, maintaining that pressure in the filter during the filtering operation, creating and maintaining a back pressure in the filter, so as to keep the filter full of beer, and collecting and carrying off from the beer any gas separating from the beer on its way from the store cask to or through the filtering apparatus, substantially as described."

These claims are each, in terms, for a process, and are all directed to the accomplishment of

"The filtration of beer in its passage from the store cask to the keg into which it is drawn for sale, without material loss of the gas contained in the beer, and without material foaming in the keg into which the filtered beer is delivered."

Drawing the beer from the store cask under a pressure exceeding atmospheric pressure, and conducting the same to and through a filtering apparatus in which that pressure is maintained, is stated, in substantially the same way, in each of the claims. This, however, would not alone keep the filter full of beer, or suffice to prevent material loss of gas, and to avoid foaming at the keg. Therefore, other and further means were necessary, and are claimed: First claim:

"Collecting and carrying off any air entering the filter along with the beer, and gas separating from the beer during the filtering operation, and discharging the filtered beer from the filter under pressure."

Second claim:

"Collecting and carrying off from the beer, during its passage from the store cask to the keg, air that may be mingled with the beer, and gas that may separate from the beer."

Third claim:

"Creating and maintaining a back pressure in the filter, so as to keep the filter full of beer."

The fourth claim comprises all the steps of the preceding claims, except that it does not include any mention of collecting and carrying off air; and, as to collecting and carrying off gas, it refers only to "any gas separating from the beer on its way from the store cask to or through the filtering apparatus."

From this analysis, it is apparent that no claim is made for any particular mode or form of apparatus. No machine is claimed, and the patent must be sustained as for a process, or it cannot be sustained at all. It is contended, however, that it cannot be sustained as a process patent, because, as is alleged, no process is disclosed, but "merely the function of a machine." This contention would be sound, if the allegation upon which it rests were well founded. The operation of a machine is not patentable. The machine itself may or may not be. If it is, a patent for it is, in effect, a patent for its operation. If it is not, no monopoly of its operative faculty can be vested in any one. The function of a patented machine belongs to the owner of the machine patent; of an unpatented machine,, to the public. A process is something quite distinct both from a machine and the func tion of a machine. It is a patentable art; and the first and original inventor of a new and useful process is entitled to protection under the patent law, without regard to any machine, or to the function of any machine, which he may employ in conducting the process. To constitute a patentable process, however, the desired result must be accomplished by a mode of treatment of the material to be affected, and not be due merely to the particular mechanism employed, or be the product simply of its operation. To determine whether a particular result is properly attributable to a mode of treatment or to the instrument employed, is often difficult, but never impossible. Where a machine is requisite to the practice of a process, both are, necessarily, in operation at the same time, and the machine contributes to the attainment of the desired result; but wherever it is discerned that there is a new method of treatment, and that the machine (whether new or old) is an instrument for the reduction of that mode to practice, the existence of a patentable process is established, no matter how greatly the machine may contribute to its performance. Applying these views to the construction of the patent in suit, I entertain no doubt that it is for a process, and that a patentable process, not merely the function of a machine, was claimed by the patentee.

2. Was Stockheim the original and first inventor of the patentable process claimed? The defendants allege that he was not, and contend that the proof which they have made with respect to the prior state of the art maintains this allegation. They have proved nine American patents, all of earlier date than the Stockheim invention, but by or in none of these was the Stockheim invention patented or described. I have examined them all, and the evidence relating to them, and cannot perceive that the process in suit was described in

any of them, or that even the Enzinger filter, (patent of November 12, 1878,) which seems most nearly available for the purpose, could be successfully used to conduct the Stockheim method of treatment. It is certain that none of them ever was so used. In some of them there may be found some part of the mechanism employed by Stockheim; and, viewed in the light which his invention has cast upon the subject, it may be seen that the end which he reached was, perhaps, almost attained by others. Still, the fact remains that the very valuable result which he accomplished never was achieved until his process gave it to the trade. The effort which has been made to show anticipation by the prior uses of the Enzinger filter, which have been proved, do not refute this conclusion. I cannot, upon the evidence, find that the process in suit was at any time substantially and successfully practiced or disclosed by any such use. On the contrary, minute and careful investigation of the Enzinger filter has fully convinced me, as already mentioned, that it does not supply means by which the Stockheim process could be successfully conducted. The Enzinger pamphlet (in evidence) gives no support to the defendant's contention. Like the patent, and the uses already referred to, it does not describe or indicate the Stockheim method of treatment. It does not show the Stockheim process, and that it does not do so is quite persuasive that neither did the Enzinger patent or uses do so. It is not necessary to pursue the subject further. I agree with the opinion expressed by Judge Gresham in Uhlmann v. Brewing Co, 41 Fed. Rep. 132, that neither the Enzinger pamphlet nor Enzinger patent "disclosed the Stockheim invention. It does not appear that the pamphlet would enable a skilled workman to construct a filter which would carry out the Stockheim process." It follows that Stockheim was an original and first inventor, if he made any invention at all. Whether he did anything involving invention, within the meaning of the patent law, depends wholly upon a question already discussed, with reference to the claims of his patents. Reverting to the principles there mentioned, and, without repeating them, applying them to the actual invention, I am of opinion that Stockheim invented a patentable process, and did not claim as an art what was merely the function of a machine. That his invention, if otherwise maintained, is useful, has not been questioned, and, I think, is not open to question. I have reached the conclusion that the patent in suit is a valid process patent.

3. Upon the whole case, the arguments, both oral and printed, were very able and thorough. They have received careful attention; but to review them at length would not be reasonably practicable. This is especially true of the exhaustive presentation of the views of counsel for the defendant in support of their contention that the complainants have failed to sustain their allegation of infringement. Without lengthy discussion of several details, it would not be possible 'to deal intelligently with the particulars involved in this question; but the result at which I have arrived, and the principles which have directed my investigations, may be very briefly stated and indicated: The machine used by the defendants is the Klein filter. The identity or equivalence of that machine, as a machine, with the apparatus used

by the complainants, is not, however, the proper subject of inquiry. The true question is: Does the defendant, as it uses that machine, practice the patented process? To this question the evidence and exhibits admit of none but an affirmative answer. The method of treat

ment is the same in each instance, and both accomplish the same result. Every step and feature of the complainants' process are used by the defendant. The complainants' allegation of infringement by the defendant is maintained. Decree for complainants, in the usual form.

PRINCE'S METALLIC PAINT CO. v. PRINCE MANUF"G CO. et al. (Circuit Court, E. D. Pennsylvania. December 23, 1892.) No. 28.

TRADE-MARKS-INFRINGEMENT-JURISDICTION OF FEDERAL COURTS.

A federal court has no jurisdiction of a suit for the breach of a registered common-law trade-mark wherein plaintiff and the principal defendants are citizens of the same state, and no charge is made of infringement in foreign commerce or commerce with the Indian tribes.

In Equity. Suit by Prince's Metallic Paint Company against the Prince Manufacturing Company and others for the alleged infringement of a common-law trade-mark. Bill dismissed.

Charles Barclay and John G. Johnson, for complainant
Richard C. Dale, for respondents.

BUTLER, District Judge. The cause of action set out is the infringement of a common-law trade-mark, registered in pursuance of the federal statute of 1881. The defense consists in a denial of our jurisdiction, and of the plaintiff's title, an allegation that he is concluded by a decision of the court of appeals of New York (31 N. E. Rep. 990.) and by laches in asserting his alleged rights. The facts involved are so well stated in the opinion of the court of appeals, (which is made a part of the record,) that no more need be said on this subject.

Have we jurisdiction? The plaintiff and the principal defendant are citizens of Pennsylvania. To give us jurisdiction it must therefore appear that a federal cause of action is set out. The breach of a common-law trade-mark is not such a cause. While registration is averred there is no charge of infringing the plaintiff's rights under it. Such registration protects the use of the mark in foreign commerce and with Indian tribes; nothing more. It would seem therefore to follow very plainly that the facts necessary to confer jurisdiction are not averred. The bill is drawn precisely as if for trial in the state courts; and presents a proper cause of action for these tribunals. It seems to have been supposed that we can redress injuries resulting from trespass on the plaintiff's common-law rights. That we cannot is clear, we think, on principle, and has been so decided. Schumacher v. Schwencke, 26 Fed. Rep. 818. Indeed the facts seem to be admitted in the plaintiff's brief at page 4.