DUNCAN, Acting Commissioner:

Question arises in this case as to the sufficiency of the account of receipts and expenditures furnished by the applicants for the extension asked for.

Among the items with which the patent stands charged, is the sum of fifteen thousand dollars for "cash expended in building and repairing buildings, and placing the necessary operative machinery therein;" the explanation of this being that it represents substantially the capital originally invested in the maufacture which the inventors established upon the basis of their patent. As the manufacture thus established is still carried on, and no corresponding entry appears on the other side of the ledger, on account of present assets, it is manifest that the above item should be stricken from the account, or rather should be offset by the present value of the buildings and the machinery.

In the table of "receipts" appears the following item:

Net profits from the sale of nine thousand four hundred and seventy-five strawcutters, made and sold under said patent, at an average price of $20 each, at the factory at Harrisburgh, from the date of issue of patent to the present date, calculated from the books at 20 per cent. on the amount sold..

$37,900 The other items under the head of "receipts" are $400 for territory sold, $3,300 for royalties, and $1,800 from miscellaneous sources.

Is this the account "in detail" which the law requires? It appears that the applicants have kept books during the whole period of their business, and, except that the business of manufacturing straw-cutters has been combined with the building of other machines, which have constituted about one-fourth of the whole business done, they undoubtedly might have given an exact and detailed statement of both expenditures and receipts on account of the patent. Instead of that they have chosen to withhold the figures upon which their calculations are based, except as to the number of machines made, and to present to the Office only the conclusion reached as to their net profits; and it is apparent, further, that even their own calculation proceeds largely upon estimates.

If the rule of practice adopted in Ex parte J. R. Harrington and Ex parte A. B. Taylor, Commissioner's Decisions, 1870, 27 and 68, were to govern in the present case, the account presented should, perhaps, be adjudged fatally defective. That element in it which is based upon the mere estimate of the parties might be held to vitiate the character of the whole. There is this fact, however, to be specially considered in this case; an opposition has been entered by rival manufacturers, who, it must be presumed, have been ready to avail themselves of any valid objection to the grant of the extension; and yet neither in their formal "reasons of opposition,” nor in the testimony taken by them, nor by argument, do they lay stress upon or even advert to this point. The inference from their silence must be construed into a concession that in this regard the statement of account is substantially correct. The averment as to the number of machines made must, of course, be deemed

reliable. If there were a material error as to price realized for them, the opposition would not have allowed the statement to pass unchal. lenged. The acknowledged percentage of profit, also, is placed so high as manifestly to preclude the chance of successfully attacking the statement on this score.

From the very language of the statute it is manifest that it is not necessary to give by itself every item of the expenditures and receipts on account of a patent which it is sought to have extended. The law requires that the statement made shall be "sufficiently in detail to exhibit a true and faithful account of the loss and profit in any manner accruing to him [the inventor] from and by reason of said invention." The object of the requirement is to furnish the Commissioner of Patents data for a reliable judgment as to whether the inventor has been reason ably remunerated; and it is only necessary that the statement of account be elaborated to this extent. Where an inventor, whose application for an extension is unopposed, has the means at hand for giving an exact and detailed statement of receipts and expenditures, but withholds the figures upon which his calculations rest, and actually gives only the results thereof, the statement must be received with great caution and carefully scrutinized, and unless supported by corroborating circumstances, may properly be rejected. But where an active contestant, thoroughly skilled in the art to which the invention relates, neither enters a demurrer to the sufficiency of the statement, nor cross-examines the applicant as to the allegations of the amounts received and expended, it may with reason be considered that the statement, as to all essential points, is to be fully credited.

Applying this principle to the present case, the statement originally presented may, so far as concerns the one point now under consideration, be regarded as sufficient. A supplemental statement has been filed, which, by calling for a reasonable allowance for the personal services of the inventors, largely reduces the net profits, as at first stated. This, plainly, has no direct bearing upon the question of the sufficiency of the statement. It relates only to the question of adequacy of remuneration, and upon this point it must be held that, in view of the large manufacture which the inventors have established in working the invention, and the fact that they have given their personal services to the businessone of them during the entire term of the patent and the other until disabled by disease-the amount realized cannot, in contemplation of law, be regarded as a reasonable remuneration.

The first claim seems to be anticipated by the references cited by the examiner. If the subject-matter of it be disclaimed, the patent may be extended.

C. WHEELER, JR., vs. C. RUSSELL AND W. K. MILLER.

APPEAL FROM THE EXAMINERS-IN-CHIEF IN THE MATTER OF AN INVENTION RELATING TO HARVESTERS.

(Decided February 26, 1872.)

Diligence-Priority of invention Joint invention-Forfeiture by public use.

The harvester being a machine in which, as a rule, practical tests of the value of an attempted improvement can be applied during only a brief portion of the year, the fact that two or three harvests are consumed in perfecting the details of a given invention does not necessarily imply any lack of diligence.

Priority of conception, coupled with diligence in reducing to practice, constitutes priority of invention.

As a rule, the question of joint inventorship may safely be left where the parties themselves choose by their declarations to place it.

When the presumption of joint invention has been created by the filing of a joint application upon a joint oath, it can be overthrown only by the most unequivocal proofs. A fortiori, will such evidence be required when it is sought, upon the legal technicality of a misjoinder of a second party with the real inventor, to affect vested rights under a patent already granted.

Whether the use of an invention in a public competitive trial more than two years before the filing of an application for a patent constitutes such a public use as, under section 24 of the patent act, will work a forfeiture of the inventor's right to a patent quære.

DUNCAN, Acting Commissioner :

The invention in controversy consists in the convertibility of a har vester from a "dropper" to a side delivery "hand-raker," the parts being so constructed and arranged that the closed platform and the slat ted apron may be readily interchanged, as the condition of the crops may require.

Russell and Miller are patentees, a joint patent having been granted them March 24, 1868, upon an application filed December 23, 1867. Wheeler's application, which is still pending, was filed October 7, 1868, six months after the date of the Russell and Miller patent.

Wheeler's testimony narrates that he conceived the idea of the inven tion in the summer of 1865, and that he made a practical application of it to a "Cayuga Chief" machine in the fall or winter following. He does not know what became of this machine, and he is not certain that it was ever used in the field. In June of 1866 he caused another machine to be built embodying the improvement, and this was put into the State trial of harvesters held that season at Auburn, iu the State of New York, being used both as a "dropper" and as a "hand-rake." In 1867 he entered upon the manufacture and sale of the improved machines, and from that date has sold about one hundred annually.

In behalf of Russell and Miller the principal facts are, that in the

month of January, 1865, they built a machine in which the side-delivery platform was made interchangeable with a slatted dropper; that this machine differed from that described in the patent only in the construction of the end-board of the platform and in the shape of the irons by which the bottom and the back of the platform were attached to the end-board; and that it was put into the harvest of 1865, working well and cutting not less than one hundred acres of grain.

The defects of this machine were that it required too much time to convert it from the one form into the other, and that the end-board was too long to serve well as a divider when the machine was used for dropping. This last defect was remedied by dividing the end-board so that the rear portion of it should be attached to and be removable with the platform; and greater facility in exchanging the platform and the dropper was secured by altering the irons by which the platform was attached to the end-board. These changes were not fully effected until the harvest of 1866, and the firm did not commence the building of machines for sale, made in all respects like that described in the patent, until the fall of 1866. For this reason Wheeler urges that they did not have the invention fully reduced to practice until after he had built the machine that was put into the State trial at Auburn, and, therefore, that he is * entitled to be regarded as the first inventor.

This conclusion does not follow. Even if it should be admitted that Wheeler was the first to reduce the invention to practice, still it appears beyond all room for doubt that Miller and Russell, or one of them, were the first to conceive of the invention, and that they used due diligence in reducing the original conception to practice. That they should have found two or even three harvests necessary to perfect all the details of the invention does not raise even a presumption of the lack of diligence, for the harvester is a machine in which as a rule practical tests of the value of any attempted improvement can be applied during only a brief portion of the year. In this case the machine was first tried in 1865. Its use at that time suggested certain modifications of a minor character, and these were made prior to the harvest of 1866. Still further changes were found desirable when the machine was again put into the field, and these other modifications were at once applied, and brought the machine into the precise form in which it was presented for a patent. In all this there was no lack of diligence; and priority of conception coupled with due diligence in reducing to practice constitutes priority of invention. It might even be said that, so far as concerns the present interference, the invention was fully reduced to practice by Miller and Russell in January, 1865; for the machine then made by them worked successfully both in the harvest of that year and in the four years following, and the modifications subsequently made in the minor details, whereby greater facility in the interchange of the plat form was aimed at, are not involved in the interference.

But it is urged again by Wheeler that, if the interference relates en

tirely to the interchangeability of the platforms without reference to the particular devices by which this is effected, Miller and Russell are not joint inventors; and that on this ground the interference should be dissolved. In support of this position he relies mainly upon Miller's testimony upon cross-examination, in which he says, in so many words, that "the invention of the interchangeable platform, so far as he knows, was made by Clement Russell; and that his own connection with the invention related to the details or minor parts, such as the application of the 'small arm' on the corner of the platform, extending into the socket or bearing, by which the inner corner of the platform is supported; also, the division of the end-board and the mode of attaching and detaching it."

This statement, however, should be interpreted by reference to the history of the invention as given in the testimony of Russell. Russell had conceived of the desirability of the interchangeable platform in the summer of 1864, before he came into communication on the subject with Miller, and he had gone so far as to have several platforms constructed during that year; but he says that he did not arrive at results entirely satisfactory, a fact which becomes specially significant in this connection, when it is considered that although his experiments were made in June and July, they did not present the invention in such form as to encourage him to put a machine into the field. It was only when he communicated his ideas to Miller, and the modifications spoken of were introduced, that the feasibility of the invention was demonstrated; and these modifications related not merely to the mode of connecting the platform to the end-board, but also provided the "small arm" upon the corner of the platform, a device which plays an important function.

In the interference of Neal & Adams vs. Daniels, Commissioner's Decisions, 1871, the perplexities connected with this question of joint inventorship were commented on, and it was then stated that as a rule the matter might safely be left where the parties themselves chose, by their declarations, to place it; and that when the presumption of joint invention has once been created by the filing of a joint application upon a joint oath it can be overthrown only by evidence of the most unequivocal character. Aside from the inherent difficulties generally connected with an investigation of the question, it is plain that the equities are all in favor of this view. The public at large would be excluded temporarily from the practice of a given invention with equal reason, whether that invention were made by two persons who are claiming it jointly or by one of them only; and when upon a mere legal technicality the public, or any member of the public, demands that an inventor be barred the exclusive use of a moiety in the right to the exclusive use of an invention which his genius has been instrumental in developing, the demand must be supported by the most positive and convincing proofs.