Opinion of the Court.

"Hand-wheels may be employed for elevating and depressing the scraping-blade in a road-machine, in combination with connections or lifting devices of other construction and arrangement from those herein shown, with beneficial results, and I so intend to employ said hand-wheels; and I have in other applications (see serial Nos. 167,212 and 173,968) for letters patent described and claimed certain combinations in which other forms of lifting mechanism are employed for effecting the vertical adjustment of the blade.

"I am aware that a railroad snow-plow or track-clearer has heretofore been patented, in which the plow was braced from the car-axle by parallel braces rigidly connected to the plow; and that a swinging transverse scoop or shovel pivoted between the ends or rearwardly-extending braces of equal length, and in connection with a wheeled carriage, has also been shown in another patent. I am also aware that other patents exhibit road-scrapers wherein braces or links are shown which connect blade-supporting standards in rear of the blade, with one of the side bars of the carriage-frame. Such devices I do not therefore herein claim, as neither of them attain the results incident to my improvement — viz., perfect flexibility of adjustment with direct support or thrust under all conditions of use and positions of adjustment."

[The foregoing words in italics were inserted by way of amendment, the disclaimer being preceded by the statement: "Regarding the 1st claim for recognition of the state of the art, insert at the end of the descriptive part of specification, page 9, the following clause, viz."]

Of the fifteen claims, the first, fourth, fifth, tenth, eleventh and twelfth were:

"1. In a machine for grading and clearing roads, the combination, with a scraper-bar or blade suspended from the carriage between its front and rear wheels, of thrust-bars extending from the axle or rear of said carriage and attached to the back of said scraper near its ends by connecting-joints that permit upward and downward adjustment at each end of the scraper-blade independent of the other, substantially for the purpose set forth."

Opinion of the Court.

“4. In a road-grading machine, a hand-wheel in combination with the blade-elevating devices, for imparting motion to said devices, when raising and depressing the blade, substantially as herein before set forth.

"5. In a machine for grading and cleaning roads, the combination, with the scraper-blade, supported by a push frame at the rear of said blade, and blade-elevating mechanism connected therewith, of a hand-wheel for imparting motion to said elevating mechanism for effecting the upward and downward adjustment of the blade, substantially as herein before set forth."

"10. In a road-machine the standards and shift L in combination with the carriage, blade-lifting devices, and operating wheels and pinions, as and for the purposes set forth.

"11. The flanged guide-roll K and flanged pinion l1, in combination with the rack J, blade D and carriage frame A, and hand-wheel M', substantially as and for the purpose set forth.

"12. In combination with the blade-elevating lever H having the internally toothed segment H', of an operating pinion I, provided with flanges, i, for guiding said segment, substantially as set forth."

The application was examined by the Patent Office, and the following objections were made:

"If claim 1 is to stand, the state of the art as shown in patents 226,686, Sweatt, Apr. 20, 1880 (self-load'g carts); 52,028, Carncross, Jan. 16, 1866; 191,287, Jefferson, May 29, 1877, and 288,261, Raab, Nov. 13, 1883 (wheeled scrapers), must be recognized.

"Claim 4 is met in patent 220,812, Day, Oct. 21, 1879 (same). Furthermore the devices of patents 297,861, Smith, April 29, 1884; 275,614, Edwards & Durkee, April 10, 1883, and 135,475, Ham, Feb'y 4, 1873 (ex. carrier).

"As to claim 5, in view of the patents 160,535, McCall, Watkins, Scott, M'ch 9, 1875, and 296,138, Cook, Apr. 1, 1884 (wheeled scrapers), the claim does not present patentable novelty, these, with the patent of Day, showing that, broadly considered, a hand-wheel and a lever are equivalent substitutes.

Opinion of the Court.

"Claims 10, 11 and 12 are met in patent of Cary, 152,072, June 16, 1874 (self-load'g carts).

"Patent 145,736, Humphreys, Dec. 23, 1873 (ex. carrier), may also be referred to as showing the state of the art in connection with claim 11.

"Claim 15 is met in patent of Carncross above cited."

Thereupon the specification was amended as before pointed out, and applicant further said:

Regarding the fourth and fifth claims, in the references cited, patent No. 220,812, it is shown that a small hand-wheel mounted on a vertical shaft and adapted for winding up a rope or chain in manner similar to a car-brake has been used for bodily lifting a diagonal scraper or snow-plow on a railroad car, both ends of the scraper being lifted simultaneously; further, in other patents it is shown that wheels having a series of projecting handles or pins are employed in connection with means for lifting the plow and conveyer in ditching machines. Neither of these devices, it is thought, embody the features which applicant desires to secure, and while there is no question but that the present wording of said claim is met by these references, yet it is believed that applicant has a point to which these former inventions have not attained.

"The claims are hereafter amended with this feature in view, viz., that in applicant's invention the wheel is designed and adapted to be worked in combination with a diagonal blade and as a balance or momentum wheel, so that a quick throw of the wheel with the hand will by the weight of the periphery of the wheel, augment the action, or carry the blade mechanism up or down to a greater extent than the mere movement of the hand."

The fourth and fifth claims were amended; the tenth, eleventh and twelfth cancelled and two others substituted; and the fifteenth was erased.

The fourth, tenth, eleventh and thirteenth claims of the patent as issued read:

"4. The combination, with a diagonal scraper supported in connection with a wheeled carriage and adapted for upward and downward adjustment independently at either of its ends,

Opinion of the Court.

of an operating-wheel (or wheels) for effecting such adjustment, adapted to act as a momentum or fly-wheel, as set forth, whereby the peripheral weight of said wheel is utilized to assist in the adjustment of the blade, substantially as hereinbefore explained."

66

10. In a road-machine, the combination of a scraper-blade adapted for upward and downward adjustment at its respective ends, an operating hand-wheel (or wheels) connected therewith for effecting such adjustment, and a brake (or brakes) acting against said wheel to arrest movement thereof and retain the parts, substantially as set forth.

"11. In a wheel road-scraper, the combination of a scraperblade adapted for upward and downward adjustment at its respective ends, an operating-wheel (or wheels) connected therewith for effecting such adjustment and adapted for developing peripheral momentum for throwing the blade up or down, and a brake acting against said wheel to arrest the movement thereof and retain the parts in position, substantially as set forth."

"13. In a road-machine, the combination, with an oblique scraper suspended beneath a carriage or body mounted on front and rear wheels, of means for imparting independent upward and downward adjustment at the respective ends of said scraper provided with hand-wheel and pinion devices for imparting movement thereto, and stops or brake devices acting in connection with said hand-wheels for retaining the parts at positions of adjustment, substantially as described."

Thus it appears that the patentee acquiesced in the ruling of the Patent Office that the application of hand-wheels to a road-grading machine, for imparting motion to the devices for raising and depressing the scraper-blade, was old, and, for the purpose of obtaining his patent, restricted his claims in this particular to momentum or balance wheels.

And it is with reference to the momentum feature, treated as an element in all the claims, that the case must be disposed of. Momentum is the quantity of motion in a moving body, and is proportioned to the quantity of matter multiplied into its velocity.

VOL. CLXIV-3

Opinion of the Court.

All revolving wheels possess momentum, but momentum wheels, so called, as balance or fly-wheels, are wheels whose momentum is utilized in the operation of machinery by a sufficient accumulation of force, through the weight and velocity of the wheel combined, to overcome the effects of temporary loss of power.

The knowledge was common that when a continuous power is applied, but the resistance to be overcome is unequal, a fly or balance-wheel will store some of the power expended during the operation and not needed at one stage, and give it out at another.

This familiar principle is thus expressed in the specification: "The rims of the hand-wheels are made sufficiently heavy to act as a balance against the weight of the blade-lifting devices, so that the momentum of the wheel will greatly assist the operator in the manipulation of the machine."

The momentum wheel of the patent is described in appellant's brief as being "a wheel having such peripheral weight, in relation to the weight of the scraper-blade to be lifted, that it will continue in rotation after the hand of the operator is removed, so as to enable him to secure a new grasp of the wheel to continue the lifting process."

Appellant's expert, Mr. Brevoort, puts it thus: "In the case of the Taft invention, the peripheral momentum was relied upon to continue the blade of a road-scraper in its upward motion so that the operator could again grasp the wheel to give further rotative force thereto without the blades falling and without the necessity of locking the wheel to enable him to get another grip thereon." And the patentee testifies: "The object of making the wheel with the heavy rim was that there might be sufficient momentum generated in the hand-wheel to make a continuous rotary motion of the wheel when it was desired to raise the blade over an obstacle, like a rock or a thank-you-ma'am,' or when approaching a cross-walk on a street. This we could not do with levers, if the lever had sufficient leverage to give this operation; and by making the rim of these wheels heavy I secured that ability to cause a continuous motion of the hand-wheel. After giving it one