4. The combination of the two pressure-bars, one of which is supported upon arms and the other upon springs, substantially as and for the purpose set forth.

It is this use of yielding pressure-bars in the combination which constitutes principally, if not wholly, the novelty of the device described in the patent. Planing-machines with a solid bed, rotary cutter, and devices for receiving and transmitting the power had been known and in use long before Woodbury claimed to have made his invention. The Woodworth planing-machine, substantially the first of the class, had all these in combination, and in the same combination as they are found in the machine to which Woodbury applied his yielding bars; but instead of bars Woodworth used rollers to keep firmly in position the wood to be planed. Woodbury merely substituted bars for rollers. No doubt the substitution was an improvement. It enabled the pressure upon the wood to be brought nearer to the cutters than it could be in the Woodworth machine. It had a more extended bearing, and therefore held the material more steady under the action of the knives or cutters, and the bars, perhaps, were less likely to be clogged by the chips cut in the operation of the machine.

On the 2d of March, 1874, the patentee sold and assigned his patent to the complainants, and they have brought this suit against the defendant for an alleged infringement.

The answer of the defendant denies any infringement and attacks the validity of the Woodbury patent for several reasons, any one of which, if sustained, must bar the relief which the complainant seeks. It is denied that Woodbury was the first and original inventor of the improvement claimed, and it is averred that the invention described in his patent had been publicly known and used for more than two years before his application for a patent was made, and that before that time his invention had been abandoned to the public. The answer contains other averments, which we think it unnecessary to set forth, because the controlling questions are, whether the device of Woodbury was the first and origi nal invention, and whether, if it was, it was abandoned to the public before he obtained his patent.

Before proceeding to the consideration of the several defenses set up, it will be convenient to refer briefly to the history of Woodbury's alleged invention. Though the patent was not granted until 1873, the earliest application for it was made on the 3d of June, 1848. The invention appears to have been completed in the latter part of the year 1846, a caveat for it having been forwarded to the Commissioner of Patents as carly as the 28th of May of that year. The petition for the patent authorized and empowered J. James Greenough, as attorney for the petitioner, to alter or modify the specification as he might deem expedi ent, and also to receive back any moneys which the petitioner might be entitled to withdraw, and to receipt for the same. Greenough, however, was not empowered to withdraw the application.

On the 20th of February, 1849, the application for a patent was re

jected in the Patent Office, and no serious attempt appears to have been made to procure a re-examination, or to renew it, for a period of more than twenty years, though during more than sixteen years of that time the improved device had been in common use. In October, 1852, Greenough, the applicant's attorney, formally withdrew the application and received back twenty dollars, of which, however, Woodbury had no notice at the time. The attorney had no sufficient authority to withdraw the application, though he had to withdraw the fee. In 1854, five years after the application had been rejected in the Office, Woodbury instructed Mr. Cooper, another patent solicitor, who was acting for him in another case, to call up and prosecute anew his rejected application. This, however, was not done. Mr. Cooper, it seems probable, was deterred from taking any action in regard to the matter by a rule which, at that time, he thought was generally enforced in the Patent Office-viz, that an application rejected, or not prosecuted within two years after its rejection or withdrawal, should be conclusively presumed to have been abandoned. This rule was not always enforced, and it was reversed by the Commissioner in 1869, and, in the Revised Patent Laws of 1870, Congress enacted

That when an application for a patent had been rejected or withdrawn prior to the passage of the act the applicant should have six months from the date of such passage to renew his application or to file a new one, and that if he omitted to do either his application should be held to be abandoned; and, further, that upon the hearing of such renewed applications abandonment should be considered a question of fact.

It was within six months after the passage of this act that Woodbury renewed his application upon which the patent was granted.

In view of this history and of the other facts appearing in the case, the question is a grave one whether the invention, even if Woodbury was the first inventor, was not abandoned by him before his renewed application for a patent was made.

It is quite certain that the action of the Commissioner granting the patent in 1873 is not conclusive of the question whether there had not been an abandonment. Under the 35th section of the act of 1870 abandonment is declared to be a question of fact. The rule of the Patent Office, though not always adhered to, had held it to be a question of law in the cases to which it was applied, and the effect of the statute was rather to change the rule than to make the decision of the Commissioner granting the patent an unreviewable decision that the invention had not been abandoned. In fact, the Commissioner may not be called upon to pass upon that question. No evidence respecting it may be before him, except mere lapse of time, and he has not generally the means of ascertaining what the action of an applicant for a patent has been outside of the Patent Office. It surely cannot be claimed that patents obtained under the provisions of the 35th section of the act are any more unimpeachable than those referred to in the 24th section. By that section the Commissioner is authorized to deal with the question

whether the invention has been abandoned, as well as with the question whether it was in public use or on sale more than two years prior to the application. Yet both these matters, as well as the originality of the in. vention, upon which the Commissioner must pass, may be contested in suits brought for infringement of the patent. Such defenses are allowed by the statute. It must, then, be open to every person charged with an infringement to show in his defense that the patentee had abandoned his invention before he obtained his patent.

It has sometimes been said that an invention cannot be held to have been abandoned unless it was the intention of the inventor to abandon it. But this cannot be understood as meaning that such an intention must be expressed in words. In Kendall et al v. Windsor (21 How., 322), this Court said:

It is the unquestionable right of every inventor to confer gratuitously the benefits of his ingenuity upon the public, and this he may do either by express declaration or by conduct equally significant with language, such, for instance, as an acquiescence with full knowledge in the use of his invention by others, or he may forfeit his rights as an inventor by a willful or negligent postponement of his claims.

To the same effect is Shaw v. Cooper (7 Peters, 292). These were cases, it is true, where the alleged dedication to the public or abandonment was before any application for a patent; but it is obvious there may be an abandonment as well after such an application has been made and rejected or withdrawn as before, and evidenced in the same manner. In Adams v. Jones (1 Fish., 527), Judge Grier said:

A man may justly be treated as having abandoned his application if it be not prosecuted with reasonable diligence; but involuntary delay not caused by the laches of the applicant should not work a forfeiture of his rights.

The patent law favors meritorious inventors by conditionally conferring upon them for a limited period exclusive rights to their inventions, but it requires them to be vigilant and active in complying with the statutory conditions. It is not unmindful of possibly intervening rights of the public. The invention must not have been in public use or on sale more than two years before the application for a patent is made, and all applications must be completed and prepared for examination within two years after the petition is filed, unless it be shown to the satisfaction of the Commissioner that the delay was unavoidable. All this shows the intention of Congress to require diligence in prosecuting the claims to an exclusive right. An inventor cannot without cause hold his application pending during a long period of years, leaving the public uncertain whether he intends ever to prosecute it, and keeping the field of his invention closed against other inventors. It is not unfair to him, after his application for a patent has been rejected, and after he has for many years taken no steps to reinstate it, to renew it, or to appeal, that it should be concluded he has acquiesced in the rejection and abandoned any intention of prosecuting his claim further. Such a conclusion is in accordance with common observation. Especially is this so when dur

ing those years of his inaction he has seen his invention go into common use, and has uttered no word of complaint or remonstrance, or been stimulated by it to a fresh attempt to obtain a patent. When in reliance upon his supine inaction the public has made use of the result of his ingenuity, and has accommodated its business and its machinery to the improvement, it is not unjust to him to hold that he shall be regarded as having assented to the appropriation, or, in other words, as having abandoned the invention.

There may be, it is true, circumstances which will excuse delay in prosecuting an application for a patent after it has been rejected, such as extreme poverty of the applicant or protracted sickness. Of such cases we are not now speaking. None of these ordinary and accepted reasons for Woodbury's inaction during the more than sixteen years that elapsed between 1854 and his presentation of the new petition upon which his patent was granted are found in this case. His first application, as we have seen, was rejected on the 20th of February, 1849, and he was then informed from the Patent Office that he could "withdraw or appeal." Nothing, however, was done until October 4, 1852, when his attorney withdrew the application and received back twenty dollars. True, the attorney was not empowered to withdraw the application, and it does not appear that Woodbury was then informed it had been withdrawn; but he was informed that the application had been rejected, and he gave no instructions to do anything more in the case, though instructions were asked, and though he was frequently in communication with his attorney, who obtained for him another patent on the 20th of March, 1849. The rejected application was suffered to rest until February 27, 1854, when Woodbury wrote to Mr. Cooper, another attorney, informing him that he had a rejected application, filed in June, 1848, for an improvement in pressure with the rotary cutter, and asking him to call up the case and get a patent for the most he could. Mr. Cooper made application for copies of the drawings and specification and for the letter of rejection, after having been informed that the application for the patent had been withdrawn, but nothing further was done, except that Cooper informed Woodbury the application had been withdrawn by his former attorney. Thus the matter rested. Cooper's connection with it ceased in September, 1854. No effort was made in the Patent Office to have the rejected application reinstated, though such an effort must have been successful had it been made, and apparently Woodbury acquiesced alike in the rejection and in the withdrawal until December, 1870, when his new application was made. During all this time he was in frequent communication with the Patent Office, prosecuting, and successfully, other applications for patents. He was not pressed by poverty to such an extent as to hinder his renewal of his application. This is shown by direct evidence and by the fact that he had means to sue for and obtain other patents. Nor was he unwarned of the danger of delay. Very soon after 1854, if not before, the use of planing machines containing pressure-bars in com

bination with rotary cutters and a solid bed was general. The defendant's answer asserts that before December 5, 1870, and since the withdrawal of Woodbury's rejected application, many thousand planing-machines containing his invention had been constructed, sold, and used in the United States, and this assertion is accepted in 'the appellant's brief. This fact must have been known by him. Upon this subject the evidence is very full. As we have seen, the distinctive element of Woodbury's invention was the substitution of yielding pressure-bars for the rollers employed in the Woodworth patent. A machine patented to Joseph E. Andrews in 1845 had those pressure-bars, and Woodbury was engaged for years in selling those machines. Between 1852 and 1854 three Cornell machines of the Woodworth patent-rotary cutter, yielding pressure-bars, combined with a solid bed-were used by John F. Keating in his shop at Boston. Mr. Woodbury was repeatedly there while they were in use, and examined them, but he never suggested that he had any claim to the use of pressure-bars in planing-machines. There is ample evidence, also, that hundreds of other machines containing the same device were manufactured and sold in Boston between the years 1854 and 1870, and were frequently seen by Mr. Woodbury, calling forth no remark from him indicating that they were invasions of his rights. In view of all this it is of little importance that from time to time he expressed a hope to his brother, and perhaps occasionally to some others, that he should some time and in some way obtain a patent. Such was not his language to the public. His inaction, his delay, his silence, under the circumstances, were most significant. Though not express avowals of abandonment. "to reason's ear they had a voice" not to be misunderstood. They spoke plainly of acquiescence in the rejection of his application for a patent. They encouraged the manufacture and sale of his invention. And there is no sufficient explanation of Mr. Woodbury's conduct-nothing which can be regarded as an adequate excuse for it. The rule of the Patent Office was not a statutory rule. It was at most only a rule of practice in the Office, and it was not inflexible. The action of the Office exhibits many instances in which departures from it were made before the act of Congress 1870 was passed, and even before Mr. Fisher, the Commissioner of Patents, abolished it. Case of J. W. Cochran, C. D., 1869. If Woodbury did not intend to acquiesce in the rejection of his application, the rule was no bar to a movement by him to have it reinstated after its withdrawal. So he might have applied for a re-examination, or might have appealed, or might have filed a new one. Thus he would have given notice that he did not intend to give up his invention to the public. There is a wide difference between this case and the case of Smith v. The Dental Vulcanite Company (93 U. S., 486). In the latter it appeared that after three successive rejections, the last in 1856, the application was never withdrawn, nor was any portion of the fee claimed. Still the applicant did not remit his efforts. He was in ill health and wretchedly poor; but he continued to assert his expectations of ultimately obtain