"Fig. 1 is a side elevation of my concentrator. Fig. 2 is a plan view, with the pulp and water boxes removed. Fig. 3 is a cross section on the line x, x of Fig. 1. Fig. 4 is a cross section to illustrate a modification in the manner of connecting the supporting links. Fig. 5 represents another modification. Fig. 6 is a cross section of the water box. Fig. 7 is a front elevation of the same. A represents a stationary supporting frame of any suitable construction, but shown here as consisting of longitudinal sills, a, a, uprights a1, a1, and transverse beams, a2, a2. B is the inclined oscillating belt frame composed of longitudinal side beams, b, b, connected by cross braces, b1, b1, and at the ends by the guide rollers, C, C1, which are journaled in movable bearings, c, c1, connected to the beams, b, b, and adjustable by means of screws, d, in order to tighten or loosen the ore belt, as may be required. A series of rollers, D, is journaled in the frame, B, over which, and around the rollers, C, C1, passes the ore belt, E. There are some features in the construction of this belt which will be hereinafter described, but at this point it is sufficient to say that it is made of suitable flexible material, such as canvas, and may be provided with riffles on its surface, if desired. The water tank, F, is situated at one end of the main frame below the high end of the belt, and a guide roller, G, is journaled in hangers suspended from the belt frame, so that the roller will dip into the tank, and carry the belt with it. The belt, after leaving the tank, passes over another guide roller, H, which directs its course to the end roller, C1. I have termed the lateral motion of the belt frame and belt an oscillatory motion, to distinguish it from the ordinary horizontal side shake, as well as from the movement produced by mounting the belt frame upon base rockers. The horizontal side shake is ordinarily produced by supporting or suspending the belt frame by vertical swinging rods, having a parallel motion, by means of which the surface of the belt maintains a constant horizontal plane as it shakes. I support or suspend my belt frame by links, I, which may be either rigid bars or wooden or metal springs. These links are pivoted to the main frame and to the belt frame, and are placed at an angle to one another (Fig. 3), so as to swing with a nonparallel motion. Either or both the pivot bearings for these links may be made adjustable, as shown at e, in order that the angle may be changed, and a greater or less variation from the horizontal plane be given the belt. In Fig. 3 I have shown these links as tending to converge downwardly. The effect of their side swing is to give the belt a swinging motion on an upward curve. But in Fig. 4 I have shown the links as tending to diverge downwardly, in which case the swing of the belt is on a downward curve. In other words, any one point on the surface of the belt moves in an arc, the direction of whose curvature relatively to the horizontal depends upon the convergence or divergence of the links, the amount of movement depending upon the angle at which the links are placed. The modification shown in Fig. 5 will be readily understood without detailed explanation. It consists simply in suspending the links from the upper part of the main frame, instead of supporting them upon its lower part. The angular relations of each pair of oppositely placed links are preserved, and the results obtained thereby are precisely similar to those just described.

"The movement of the upper part of the belt, when the links are arranged as shown in Fig. 3, is like that of a belt supported upon rockers working upon a base; but there are important advantages attending my construction. Where rockers are employed, the amount of transverse movement out of the horizontal given to the belt is constant and unchanging, because it depends upon the curvature of the rockers and the throw of the crank which operates them, and these are fixed at the time of construction. In my device, the adjustment of the links to different angles enables me to change, increase, or diminish the vertical movement of the belt within limits only fixed by the amount of slide that can be given at the pivotal connection of the links. Another advantage is that the amount of lateral swing on a curve, given to the roller suspended in the water tank, is very much greater than can be given such a roller by means of a rocker which works upon a pin at its contact point, where the motion is very slight. I am thus enabled to more thoroughly wash the belt in the tank, and more effectually to clear it from the sulphurets, some

of which might otherwise escape, and be washed off by the water flowing down the incline, and lost. The lateral oscillation of the belt frame is imparted by pitmen, J, connected to cranks, J1, upon the driving shaft, K, which is journaled in bearings upon the stationary main frame. The pitmen extend across the belt, and are connected to the side beam of the belt frame. The shaft, K, which carries the driving pulley, L, is connected by a belt, M, running on two cone pulleys, N, O, to the counter shaft, P, which is the driving shaft for giving the longitudinal or 'uphill' movement to the belt. By using these cone pulleys, I am enabled, by shifting the belt, M, to change the speed of the shaft, P; and to accomplish this easily, and at the same time provide a belt tightener, I journal the shaft, P, in adjustable boxes. f (Fig. 1), by means of which the strain on the belt may be increased or diminished, as required. The shaft which gives the longitudinal motion to the belt is composed of two parts, P, P1, the latter being journaled in a bearing in the belt frame, and having a worm, g, engaging with a screw gear wheel, h, on the journal of the driving roller, C. As the main part, P, of the shaft is journaled in the stationary main frame, while the part P1, driving roller, and gearing must swing with the belt frame, a length of flexible shafting is interposed, and connected by couplings, i, i, to the two parts of the shaft, P. Any kind of flexible shafting may be used, but I prefer to employ a sufficiently stiff piece of wire rope or cable, which is well fitted for the purpose. Journaled in the sides of the belt frame, and alternating with the rollers, D, is a series of cones, Q, mounted upon short stub axles, j. (See Fig. 4.) The purpose of these is to turn up the edge of the belt as it passes over the rollers, D, and thus form a continuous flange to retain the pulp, and prevent overflow at the sides. Such cones have been used before for the same purpose. but have always been formed with the rollers, D. The result was that the difference in speed, produced by the difference between the diameters of the roller and the cone, would cause a drag on the belt, and its consequent wear. By making the cones separate and independent, both cones and rollers take simply the speed of the belt, and there is no unequal strain upon the latter. R represents the pulp box supported by standards, k, on the belt frame, and shown as provided with a series of orifices, 1, in front, to distribute the pulp to the belt.

"I have heretofore referred to the belt as composed of canvas or like textile material. In order to preserve the belt from wear and the liability to decay, I boil or soak the canvas in a weak solution of glue, gelatine, or other animal fiber, which thoroughly permeates it. I then boil it in tan-bark water, which converts the gelatine into tannate of gelatine, and produces a textile fabric of great durability, and which also resists decay. S (see Figs. 6 and 7) represents the water box situated in front of the pulp box, and supported by an arm, 11, connected to the main frame. The front board, m, of the box has its upper edge perforated a sufficient distance with a series of vertical holes or At the bottom of this series, and intersecting the holes compospassages, n. ing it, is a series of horizontal holes or passages, o, extending entirely through the board, so as to let water pass from the interior of the box. Each of the vertical holes, n, is provided with a screw or plug, p, by means of which the water may be entirely shut off from each passage, o, or allowed to run freely therefrom, and otherwise regulated. The water escaping from the holes, o, is conducted to the belt by vertical grooves or 'saw cuts,' q. extending down to the lower edge of the front board; the latter being beveled to a sharp edge, r. to prevent the water from finding its way backward along the bottom of the box. This is an exceedingly cheap, simple, and effective way of constructing the water box, and of regulating not only the amount of water supplied to the belt, but its proper distribution over the surface."

Claims 1 and 2, said by complainant to be infringed by respondent, are as follows:

"(1) In combination, a belt frame, means for sustaining the same, consisting of links, I, at its opposite sides, pivoted to the belt frame and the main frame. to have movement laterally thereof only, said links being permanently set at an angle to each other, and means for moving the frame on the angularly ar

ranged supporting links, substantially as described. (2) In combination, a belt frame, means for supporting and directing the movement of the same, consisting of the links, I, having movement transversely of the frame only, said links being set permanently at an angle to each other, and being capable of adjustment to vary the said angle, and the means for moving the frame, substantially as described."

The respondent, in his amended answer, sets up the defenses of want of invention and anticipation, and denies the charge of infringement. In support of the defense of anticipation, reliance is made upon the following prior patents: No. 325,129, dated August 25, 1885, granted by the United States to E. W. Stephens, for improvements in ore concentrators, and No. 285,110, dated September 18, 1883, to John M. Adams and William F. Carter, for improvements in ore concentrators; also upon the printed pamphlets published and put in general circulation by the said Adams and Carter for the purpose of advertising and selling their patented machines under the name of the "Frue Concentrators." A list of mines is also set forth at which the said Frue concentrators are alleged to have been used prior to complainant's patent.

The primary question to be determined is the validity of complainant's patent. What is the essential idea or conception embodied therein? As stated in the specification, the improvements consist in a novel manner of connecting the belt frame carrying the moving belt to the stationary main frame, so as to produce an oscillatory motion of the former, and means for changing the degree of such oscillation. The method of operation is the following: The supporting strips pivotally connecting the belt frame with the stationary frame at the four corners are angularly inclined. Mechanism is provided for giving a lateral motion to the belt frame, and the surface of the belt is given an oscillatory motion by the swinging of the supporting strips, the degree of oscillation depending upon the divergence or convergence of the links or supporting strips. The state of the art at the time complainant applied for his patent discloses ore concentrators having a lateral movement of the belt frame, effected by various mechanical devices. The greatest reliance is placed by respondent upon the Carter and Adams patent as anticipating the patent in suit. The Frue Company now own the Carter and Adams patent, and all machines manufactured in accordance with that patent are commonly known as "Frue Concentrators." The accompanying drawings illustrate the device, and are explained as follows: