delivered the opinion of the Court:
This is an appeal from the Commissioner of Patents in an interference case, wherein the subject-matter of controversy *560is the question of priority of invention of an improvement in machines for sawing timber, which is described in four issues formulated in the Patent Office, as follows:
“ 1. In a gang-edger, the combination of a saw-arbor, a series of saws mounted thereon, a series of slides of like form and dimensions having their outer ends at an angle to the body of the slide, and connections between said slides and the saws.
“ 2. In a gang-edger, the combination of a saw-arbor, a series of saws mounted thereon, a series of slides of like form and dimensions having their outer ends at an angle to the body of the slide, an arm connected to each of said slides, a guide for said slides and arms, and connections between said slides and the saws.
“ 3. In a gang-edger, the combination of a saw-arbor, a series of saws mounted thereon, guides or ways adjacent to said arbor, a series of slides of like form and dimensions, mounted on said ways, said slides having a straight body portion with their outer ends bent at an angle thereto; an arm extending from each of the slides at an angle to the straight portion and in a direction opposite to that of the bent portion of the slides; a guide for said slides and arms, and connections between said slides and the saws.
“ 4. In a gang-edger, the combination of a saw-arbor, a series of saws mounted thereon, guides or ways, a series of slides of like form mounted thereon, said slides having their outer ends bent at an angle substantially as described, arms extending from the under face of the slides to one of the guides, means for holding the slides in their adjusted position, and connections between said slides and the saws.”
A gang-edger is a gang or combination of circular saws for splitting and edging boards; or, as it is defined in the Century Dictionary, it is “ a machine having from' three to six circular saws on a common mandrel, capable of being so adjusted as to split wide planks into boards or scantlings of the width required.”
It is a machine well known and widely used in the lumber regions of the Western States of our Union. ‘ In the issues *561above recited, wbicb are taken from tbe claims of tbe application of the appellant Alpbeus E. Roe, a complete gang-edger is described; but tbe subject-matter of tbe controversy between tbe parties, and tbe subject of invention here, is greatly more limited. It is merely the shifting device for adjusting tbe circular saws into their desired positions. Tbis adjustment is effected by tbe use of band-levers.
Tbe appellant Alpbeus E. Roe, who is tbe junior applicant, alleges in bis preliminary statement tbat be conceived tbe invention, first made drawings of it, and disclosed it to others, on or about November 1, 1898; tbat on or about May, 1899, be showed and explained these drawings to bis opponent, tbe appellee Dempsy B. Hanson; tbat be first embodied bis invention in a full-sized machine wbicb was completed and operated before August 1, 1899, and wbicb was at tbat time examined by Hanson; tbat, on March 19, 1900, tbis machine was successfully operated and used in tbe city of New Whatcom, in tbe State of Washington, where tbe appellant resided; tbat be has since continued to use tbe same; and tbat be has also manufactured another machine for use in tbe sawmills of tbe company by wbicb be was employed, tbe Bellingham Bay Improvement Company. He filed bis application for a patent on January 2, 1900.
Tbe appellee Dempsy B. Hanson in bis preliminary statement alleges tbat be conceived tbe invention on or about March 25, 1899; tbat be communicated it to others about April 1, 1899; tbat be made drawings or sketches of it about April 15, 1899, or rather tbat be caused such drawings or sketches to be made by a draftsman for him; tbat the invention was commenced to be embodied in full-sized operative form about May 1, 1899, and completed in tbe early part of July, 1899; and tbat other machines have since tbat time been in public use.
Hanson’s application for patent was filed in tbe Patent Office on September 6, 1899, and letters patent were issued to him on January 9, 1900, seven days after tbe filing of Roe’s application, and probablv in ignorance of tbe filing *562of that application. At all events, although a patentee, he cannot, as against Noe, be entitled to any special advantage from his patent. He is, however, the senior applicant; and, as such, he is entitled to have the burden of proof placed upon his opponent Noe. This was the relative position in which they were placed by the Patent Office.
Upon the testimony and the record made for themselves by the parties, the examiner of interferences and the board of examiners-in-chief held that the appellant Noe was entitled to judgment of priority of invention. But upon appeal to the Commissioner of Patents, the assistant Commissioner, who sat in his place, reversed the decision of the board, and awarded judgment of priority of invention to the appellee Hanson. By all three of the tribunals of the office it was held that Noe was the first to conceive the invention, but second to Hanson in his reduction to practice. The decision, therefore, turned upon the question of the due diligence of Noe; and in this regard the examiner of interferences and the board of examiners held in his favor, and the assistant Commissioner against him.
Prom the decision of the assistant Commissioner the applicant Noe has appealed to this court.
That the appellant Noe was the first to conceive the invention in controversy may be assumed as the result of the testimony in the case. It is so held by all the tribunals of the Patent Office, and is not very seriously controverted on behalf of the appellee Hanson. We deem it unnecessary, therefore, to examine the testimony so far as it relates to this point. The conception and disclosure are shown to have occurred in November, 1898.
The appellee Hanson’s conception and disclosure are not claimed t.o have occurred until about April 1, 1899, five months after the disclosure of the invention by Noe. Undoubtedly, therefore, in the matter of conception of the invention he was anticipated by the latter. The difficulty in the case is as to the question of reduction to practice, and as to the diligence of Noe, if it should appear that Hanson was the first to reduce to practice. If there were no *563actual reduction to practice by either party before September 6, 1899, the date of the filing of Hanson’s application, the latter would be entitled to priority of first constructive reduction to practice. But there is proof tending to show actual reduction to practice by both parties before that date.
Both parties were evidently working at the invention during the same period of time, the spring and summer of 1899. Hanson was undoubtedly the more diligent about this time; although there may have been a special motive for his activity, if the attempt on the part of Hoe to show that Hanson derived the idea from disclosure to him by Hoe about May 1, 1898, be regarded as successfully shown by the testimony. On this point, however, it is unnecessary to express an opinion.
It seems that about the end of April, 1899, Hanson communicated his idea to the Vulcan Iron Works, a company which constructed machines of this general character, and that drawings were made for him by a draftsman in the employment of the company. Thereupon during the months of May, June, and July, a machine embodying the invention was built by that company at its factory, in the city of Seattle, in the State of Washington, which was sold on July II, 1899, to the Hock Greek Lumber Company, and thereafter used by this latter company. Hanson at this time had no specially engrossing occupation;-while Hoe, who was a mechanical engineer in the service of a company known as the Bellingham Bay Improvement Company, with its headquarters at New Whatcom, in the same State, was an extremely busy man, and could only give his attention to the invention at odd moments when his time was not demanded by the service of his company. After his conception and disclosure of the invention in November of 1898, it is shown that he worked diligently enough in the preparation of drawings, which he finished in April or May of 1899; and thereupon that he commenced forthwith the construction of a machine embodying the invention, which was finished in August of 1899. He was occupied at the time in the restoration of a mill for his company which had been de*564stroyed in June of tbe previous year. He first constructed a small mill, and thereafter a larger one. The gang-edger, which he had procured to be finished in August he was desirous to place in the first or smaller of the two mills, which was finished soon afterward; but the officers of the company preferred to have their old gang-edger repaired and used in this mill. The gang-edger with the appellant’s shifting device was placed in the larger mill subsequently completed and was first operated in that mill in March of 1900. This was the first commercial test of it; but it had already been operated in such manner as to show its practicability, and it was and remained in condition adapted for practical operation.
Under these circumstances we cannot hold that there was any want of diligence on the part of the appellant. His device was complete and embodied in a full-sized machine adapted for practical application in August of 1899. For the failure to test it by putting it forthwith into practical commercial use, there is sufficient reason shown. It was tested in fact at the time and shown to be operative; and when it was finally put to the test of actual commercial use, it was shown that there was nothing wanting to its practicability. We think that in this regard this case falls within the principle of the case of Mason v. Hepburn, 13 App. D. C. 86; Lindemeyr v. Hoffman, 18 App. D. C. 1.
The examiner of interferences and the board of examiners-in-chief are not clear that the constrction of Hoe’s machine in August of 1899, without actual test of it by commercial use, was reduction to practice; and the Commissioner in great measure basing his opinion upon the theory that Hoe’s reduction to practice was not earlier than the filing of his application on January -2, 1900, holds that there was too great delay and want of due diligence on his part. We are of opinion that the construction of his machine in August of 1899, was actual reduction to practice by him, that the delay in using that machine commercially and thereby testing it by actual use was not unreasonable *565-under the circumstances, and that there was no want of dne diligence on his part between his conception and disclosure in November of 1898 and his actual reduction of the invention to practice in August of 1899. And being of this opinion we must hold, in opposition to the decision of the assistant Commissioner, that judgment of priority of invention should be awarded to the appellant Alpheus E. Roe.
The clerk of this court will certify this opinion and the proceedings in this court in the premises to the Commissioner of Patents according to law. Reversed.