(after stating the facts as above).
[1] A comparison of the defendant’s construction with that of the complainant leaves no doubt in my mind that the claims sued on are responded to substantially, and in most instances literally, by the defendant’s construction. The differences pointed out by the defendant in the framework, in the substitution of a slide for rollers at the receiving end of the elevator, and the use of rollers 59 in the defendant’s construction, are all immaterial changes, and do not depart from the substance of the complainant’s invention, if there be such. The defendant’s contention that the spring arms of its elevator are merely centering arms is not well taken. The spring arms employed by the defendant are identical with those illustrated in complainant’s patent No. 881,042, and are correlated with the same elements essential to the production of the result obtained. The proof shows that the defendant’s spring arms serve to prevent the movement upon the inclined section of the elevator of boxes riding upon the flights, retarding their movement until properly engaged by the succeeding flight.
Nor has the defendant succeeded in its direct attack upon the complainant’s invention. None of the many prior patents and structures in evidence seems to me to anticipate the substantial advance in the art embodied in the claims in suit. Some of the elements of the patented structure may be old, but the result obtained by the combination and correlation was new and efficient beyond anything that-had been known before. The evidence clearly establishes the utility and commercial value of the complainant’s invention. The old method of handling heavy packages by hand trucks and straight lift or plat form elevators was slow, ruinous to floors, involved much breakage, and required a great deal of manual labor and attendance. The complainant’s structure overcame these disadvantages. Prior gravity carrier systems were limited in range to situations where packages were to be transferred to a lower level. The complainant’s structure *578eliminated such restriction. By its use packages are automatically transferred to points at the same or a higher or a lower level, irrespective of the distance between the delivery and receiving points, and this result is accomplished automatically by a single and simple mechanism, which is operated with a minimum of labor or attendance. It co-operates with the gravity conveyor sections without manual aid to receive packages without shock or jar from the lower sections, and without the necessity of any times relation between the periods of arrival of the packages at the elevator ánd the phases of movement of the propelling devices of the elevator. The elevator is always ready to perform its function as a part of the system. The complainant’s structure is not to be dissected in an effort to discover anticipation in old and often crude devices designed for different purposes, and which are similar to the complainant’s mechanism only in that they may be broadly termed inclined endless conveyors for elevating freight.
[2] Finally, the defendant raises an issue of abandonment by reason of alleged public use and sale for more than two years prior to the date of the application for patent No. 881,042. It is claimed that the spring arms covered by the patent had been used on a machine exhibited and put on sale by the complainant at the St. Louis World’s Pair in 1904. I find from the evidence that the complainant’s exhibit «rt the World’s Fair included the elevator forming the subject-matter «af patent No. 790,811 in suit, and that during part of the time it was exhibited with spring arms. But such use was experimental, and the tests then made were not successful. The elevator thus used was not on salé. At the close of the Fair this elevator was dismantled, shipped back to the complainant’s factory, and was not again erected. It was not until January, 1906, that further experiments with spring arms were made, when, proving successful, an application for a patent therefor was filed on October 6, 1907. The construction covered by complainant’s patent cannot, therefore, be said to have been in public use or on sale for more than two years prior to the date of application. The printed circular containing a reproduction of a photograph of the complainant’s exhibit shows the spring arms; but inasmuch as they can hardly bé discerned, with the aid of a magnifying glass, and the circular contains no description of their construction and operation, it is clearly not such a publication as will invalidate the patent in suit.
The complainant may have a decree.