Complainants are owner and its licensee oT United States patent No. 835,120, for improvements in a process of ore concentration, issued on an application filed May 29, 1905, by said owner’s grantors, Messrs. Sulman, Picard, and Ballot, of Uondon, England, joint inventors and patentees, and this suit is for infringement of certain claims of said patent by defendant, a former employe of said owner, and by it trained in the process. The defenses are various grounds of invalidity, hereinafter noted so far as of merit and seriously urged, and noninfringement.
The invention claimed, in general terms, may be said to be the discovery, in March, 1905, that if a very small and appropriate quantity of an oily substance, ranging around .02 per cent, to .5 per cent, of the weight of the ore he added to a pulp of water and finely pulverized ore (the slimes being helpful and most easily recovered), and the whole vigorously agitated and thereby thoroughly aerated by great and excess quantities of air, the metalliferous particles are oiled and adhere in a complete envelope to or of bubbles of the air, and rise to the surface of the mixture on cessation of agitation, forming a strong, coherent, and stable froth easily removed. The process may be aided by heat to more quickly and effectively disseminate the oily substance through the pulp, and bring it into contact with the metalliferous particles, and may also he aided by a mineral acid or salt up to 1 per cent, thereof of the weight of the ore to increase the preferential affinity of the 'oil for metal over gangue, but not sufficient acid to cause chemical action on the metal, nor is it intended to generate gas for flotation. The patent specification is full, complete, and clear to those skilled in the art, and describes one well-known apparatus of mixing vessels, spitzkasten, etc., and the operation of the process therewith.
The claims are general and particular, all calling for oil and agitation to produce a froth, some defining a range of quantities of oily substance, some likewise of acid, some specifying oily substance alone, some oily substance in various combinations with heat or acid anil with both. The main defense of invalidity is' lack of novelty and anticipation. In reference thereto it appears from the evidence that the use of oil, air, and agitation in ore concentration, separately and in various combinations, and with other ingredients, was well known to the art prior to the discovery of the process in suit. To briefly summarize the prior processes, some of them were bulk oil processes, using oil in such large quantities that, il taking up the metalliferous panicles in the pulp the mass thereof was yet sufficiently buoyant to float to the surface of the water, the gangue sinking. Concentration being more essential for lean ores, economy is the foundation of success ; so other of these processes reduced the amount of oil to a degree where it was not sufficient of itself to float the metal, and to aid therein air, steam, or gas was injected to render the mass spongy. Another *958process further reduced the oil, and to around 4 per cent, to 6 per cent. in weight of the metalliferous content of the ore, the somewhat novel result being that the metalliferous particles were by the oil agglomerated into granules which sank in the water and were x-etained in the -mixing vessel, while the gangue rose and was carried off by upcast. Soxne dispensed with oil, -and employed surface texrsion or skin flotation by floating off the powdered metalliferous particles on the surface of quietly flowixig waters, or by ixrjecting air, steam, or gas into the mixtux-e of ore and water, or by generating gas therein, whereby bubbles attached to said particles and carried them to the surface of the water, in all the gangue sinking. Another process sought the same end by spraying the oiled metalliferous particles through the air and oxito water, where they remained, the gangue sinking. In some processes acid was used to generate gas in situ for flotation, while in others it was used solely to render more pronounced the selective attribute of oil for metal over gangue. This last feature was the discovery, so far as ore coxicentration is concei'ned, of Cax'rie J. Everson, of Chicago, to whom a domestic patent embodying it was issued in 1886. In soxne heat was used to hasten the action of the oil, and some resorted to agitation..
For anticipation, defendant relies most upon Froment’s patents and working description. They date from 1902 and 1903. The process thereof is one wherein the ore is carefully crushed in two operations so as to minimize slime, and is first deslimed, for that the slime, is “too fine to be treated,” quoting Froment. Thereupoxi to a mixture of deslimed ore and water, oil axid carbonate of lime (which xnay be lixnestone) are added proportionate to the weight and richness of the ore, from 1 per cent, of oil in weight of the ore for ore contaiixing up to 5 per cent, of metal, to 3% per cent, of oil for ore containing 50 per cexit. of metal, and about 1 per cent, of carbonate of lime in weight of the ore, or 2% per cent, in difficult cases, or more, and in like proportions to the oil for richer ore, it requiring more gas. Agitation in mixers containing two stirrers revolving in opposite directions and for a few xnixiutes, or about 10 minutes, at about 300 revolutions per xninute, the "chief point” being that all metallic particles are brought “into thorough contact with the oil,” is described by Froment. The mixture is then discharged into a vat containing a perforated coil through which sulphuric acid is introduced and in quaxxtity about cent, per cent, of the cax'bonate of lime, and a rake therein txxrns slowly and about 10 to 12 revolutions per minute, to pi-event- the ore collecting-at the bottom in too compact a mass-.
Steam may also be-injected through said coil to assist the reaction, but it is necessary in only cold countries. The reaction of the acid generates gas which in hubbies carry the sulphides to the surface, there skimmed or pushed into a hopper. Such thereof as fall back and sink are otherwise recovered. A large proportion of the oil may be recovered from the concentrates in a press. Froxnent’s patents refer to the use of "gas of any kind,” that the bubbles will “become covered with an envelope of sulphides,” and, rising to the surface, “form a kind of metallic magma,” and that the “formation of these *959metallic spherules is singularly active if the gas is in a nascent state.” Fromeut's patents, working description, and an apparatus therefor were purchased in 1903 by the patentees of the patent in suit. It may he noted that prior to said purchase, and continuously since, said patentees were and now are associates and metallurgists, chemists, experimenters, inventors, and operators in ore reduction in various parts of the world, with headcpiarters in London. To 1hem and in that behalf have issued patents, domestic and foreign, and they have purchased others. They are of complainants, and much of their work has been for complainants. There is little evidence of practical use of any of these prior processes, and no substantial evidence that any substantial commercial success has accrued to any of them, or that any of them has had any considerable continuous successful operation. Some have operated commercially with some small success, and some are long since abandoned as impracticable, experiments, failures. Froment's process has not been in practical operation.
Complainants’ process has, in instances, displaced some of the prior, and has firmly established itself as a new and valuable method of ore reduction. The evidence shows many and large plants thereof, built or building, in widely separated parts of the world. Its successful operations, practically from discovery, have recovered, and largely from waste and tailings, values aggregating near $9,000,000, and at a profit of near $4,000,000 to the patent owner and its licensees. Detailed comment in respect to anticipation is little necessary save to Froment. Looking to the evidence, and therefrom contrasting his process with complainants’, Froment’s requires several times the quantity of oil that does this in suit, both by examination of the patents and working description and by tests in evidence. Froment crushes the ore in two operations, and deslimes it before treatment because the slime is too fine to be treated by his process, while the process in suit needs but one crushing operation, and finds slime advantageous and most easily recovered. Froment employs carbonate of lime; the process in suit does not. Froment requires acid, and in greater quantity and for a different function than does the process in suit, which latter may or may not use acid. Loth may use heat, and both require agitation, Froment, agitation only to disseminate the oil, the process in suit for that purpose, and also to aerate. Froment’s result is by flotation by gas generated in situ; this in suit is by flotation by air introduced by vigorous agitation. Froment’s product is like unto a magma, a spongy, pasty mass of oil and metallic particles, and more or less gas bubbles, while this in suit is a froth of oil and metallic particles and air bubbles. Froment’s requires oil in such quantity that he deems it worthy of recovery from the concentrates so far as it can be; this in suit so little oil it disappears, is not sensible to sight or touch upon the concentrates, but only to analysis. In Froment’s it would seem that the metallic particles are floated like the basket of a balloon, while in tliL, like the very envelope of a balloon. Froment’s is costly, while this is cheap—relatively. And from the evidence it would seem that Froment’s process would fail in practical operation, while this in suit has *960succeeded. In Froment’s, he oils the metallic particles by agitation, then when the mixture is quiescent, generates gas therein by quick reaction followed by immediate and direct rising of the gas bubbles to the surface in which they may come into contact with but few metallic particles. In this in suit vigorous agitation of the mixture beats great and excess volumes of air therein, likely bringing the ultimate air bubbles into repeated contact with many metallic particles. The action of the gas in Froment’s is almost explosive in nature. He speaks of a proportion of carbonate of lime to be sought, as in his test tube example the reaction may be so sudden and violent as to project the metallic particles out of the tube. Froment’s gas bubbles, quick formed and quick rising; it may be arrive at the surface with expansion still in progress. These or analogous reasons may account for Froment’s magma, breaking gas bubbles, and fragile evanescent froth in so far as his result is like unto froth, and also may account for the process in suit’s strong'and lasting froth.
One of the complainant’s experts, Dr. Adolf Diebman, of London, characterizes Froment’s product as not a froth but a magmá, and his process as one involving the principles of skin flotation assisted by bubbles of carbonic acid. He further testifies that in the process in suit is produced a result which was never obtained before; that the froth is of a peculiar character, “consisting of air bubbles which, in their covering film, have the minerals embedded in such manner that they form a complete surface all over the air bubbles”; that though “the very light and easily destructible air bubbles are covered with a heavy mineral, yet the froth is stable and utterly different, so far as this property is concerned, from any froth known” to him; that “it appears as if the minerals were protecting the tender air bubble like an armor guarding it,” so that “the froth has a long life,” and one is “tempted to say'it is permanent, at least as far as metallurgical operations are concerned”; that he himself had “seen a froth standing for 24 hours without the least change having taken place”; that a “very striking difference between the previous processes and tire process of the patent in suit is the difference between failure and success”; that “the simplicity of the operation as compared with the prior attempts is startling.”
Another of complainants’ experts, Dr. Charles F. Chandler, of New York, testified that the process in'suit is new and surprising; that “there is nothing like it disclosed in the prior art.” These and other learned gentlemen gave at length reasons for the foregoing and like views and conclusions. Defendant’s expert, Dr. Eugene A. Byrnes, of Washington, is to the contrary.
[1] The differences hereinbefore set out between Froment’s process and this in suit are so* obvious, numerous, radical, and in many respects vital, it is clear they constitute different processes. They are different in ingredients, function of some thereof, confbination, manipulation, principle, and result. Their points of resemblance only serve to accentuate their difference. Broadly speaking, a process is a definite combination of new or old elements, ingredients, operations, ways, or *961means to produce a new, improved, or old result. Any substantial change therein, by omission to the same or better result, or by modification or substitution with different function to- the same or better result, is a new and patentable process. New or substantially changed methods whereby the product is bettered, increased, cheapened, may be a new and patentable process. Thus are the cases. See Mowry v. Whitney, 14 Wall. 640, 20 L. Ed. 860; Dental Co. Case, 93 U. S. 494, 23 L. Ed. 952; Tilghman v. Proctor, 102 U. S. 722, 26 L. Ed. 279; Loom Co. Case, 105 U. S. 587, 26 L. Ed. 1177; Lawther v. Hamilton, 124 U. S. 6, 8 Sup. Ct. 342, 31 L. Ed. 325; Richards Case, 159 U. S. 485, 16 Sup. Ct. 53, 40 L. Ed. 225; Steel Co. Case, 185 U. S. 420, 22 Sup. Ct. 698, 46 L. Ed. 968; Expanded Metal Case, 214 U. S. 384, 29 Sup. Ct. 652, 53 L. Ed. 1034; Rubber Co. Case, 220 U. S. 443, 31 Sup. Ct. 444, 55 L. Ed. 527.
In this suit the doctrine of equivalents has no application. The process in suit is so clearly new that no exhaustive discussion of facts, cases, or law is necessary to distinguish it from other processes, or to demonstrate its novelty. The patentees herein discovered a new, cheap, simple, practical, and useful way or process to combine oil and air, and by agitation to float and secure the metallic content in ore concentration. The argument that the prior state of the art was such that to any one skilled therein the process in suit at the time of its discovery was obvious may, under the circumstances, be well answered by the cases:
"Kuowleclge after the event is always easy. * * But the law has other tests of invention than subtle conjectures of what might have been seen and yet was not.” Rubber Co. Case, 220 U. S. 435, 31 Sup. Ct. 444, 55 L. Ed. 527.
See Expanded Metal Case, 214 U. S. 381, 29 Sup. Ct. 652, 53 L. Ed. 1034.
[2] To whatever extent the patentees herein drew from the prior art, as they rightfully could, they took the last and successful step. It is urged, however, that as the patent in suit does not specify exact quantities of oil and acid, but a range thereof, it describes merely an experiment not patentable. It is true every ore presents its own problem of reduction. So, while all may lend themselves to a general method, each may require some modification of the method. All skilled in the art understand this, and know that in addition to the best scientific theory they must add the light given by trial and practice. Thus only, in the majority of cases, are good and the best results obtained in any ore reduction-—smelting, milling, or concentration. It is believed that at least in cases where the combination or process is not of itself the result sought, but only the means thereto, a range of quantities that leaves something to the judgment of the operator is all that can be described, and is sufficiently definite. See Mowry v. Whitney, 81 U. S. 646, 20 L. Ed. 860; Wood v. Underhill, 5 How. 5, 12 L. Ed. 23. The patent for an ore reduction process that does not is a rarity indeed. To the' contention that as in Eroment’s process the agitation must entrain some air like unto that of complainants’, and *962so the latter lacks novelty, it may be observed that if so, it was unintentional and unrecognized, in that Froment had in mind only flotation by quick acting gas generated in situ, it aided the art none, and is unimportant. See Tilghman v. Proctor, 102 U. S. 711, 26 L. Ed. 279.
And to the argument that in operating Froment, in rightful economy and decrease of oil and in rightful omission of carbonate of lime in treating ore containing it in sufficient quantity, his process would approximate this in suit and arrive at a like froth, and hence lack of novelty in' the latter, the response is that the fact that infringement may be easy does not impeach an otherwise valid invention, and that if Froment’s methods are modified until they approximate complainants’ and produce a like product, the px-ocess is no longer Froment’s but is complainants’. At the argumexit, with apparatus a number of tests and demonstrations were made in the presence of the court, both of the process in suit, of Froment’s, and of others of the pribr art, of much assistance in arriving at conclusions herein.
Upon all the evidence the court is of the opinion the defexrse of lack of novelty and anticipation is not established.
[3] Another defense is that the invention is xiot joint. It seems the patentees were experimenting with the Cattermole Granulation process. An experimenter in their employ, in obedience to their instructions detex'inined on by consultation between all said patentees and to which ' each contiflbuted suggestions, gradually reduced the axnount of oil until the result was the peculiar froth of the process in suit. He frequently reported to his employers, who fx-equently observed his labors, and they made a record thereof in the form of reports by two of them to the third, who was chairman of the owning complainant herein, and for whose ultimate benefit the experiments were conducted. This experimenter was but the instrument through which the genius of these patentees found expression. The circumstances are sufficiexit to constitute these patentees joint discoverers. At any rate, it is not proven they are not. Although some of the claims in issue include elements not absolutely essential, viz., heat and acid, and in respect to which they may afford no protection, they are not invalidated by undeceiving superfluous features, if heat and acid are such. The patent is valid in respect to all claims in issue.
[4] In the matter of the defense of noninfringement, it appears when the charge of infringement was brought to defendant’s knowledge he refused to permit an agent of complainants to inspect his plant. This agent later secured brief access at night, observed, noted, and carried away some of the froth then being produced. This agent is a mining engineer and metallurgist. He describes the defendant’s plant, and gives it as his opinion, being versed in complainants’ process, that the process therein was substantially that of complainants. Dr. Chandler analyzed the froth so secured, and found its components practically the same as those of froth froxn samples of some of defendant’s materials thereafter furnished and treated by complainants’ process, and Dr. Chandler pronounced it as his opinion, based thereon, on the testimony of the agent aforesaid and on his knowledge of complainants’ *963process, that defendant's operations were of complainants’ process. Defendant, pending this suit, filed an application for and procured the issue of a domestic patent for a flotation process like to this in suit, which Dr. Leibman testifies “contains a description of the process disclosed in the patent in suit,” and "'discloses an apparatus for carrying on the process in suit.” And so doth it seem to- the court. Although defendant testified, he professed ignorance of the amount of oil and acid used in his plant and operations. Enough appears in the evidence to compel the conclusion defendant was using complainants’ process and was infringing the claims in issue as charged.
It is worthy of note that during the taking of testimony complainants repeatedly offered to repeat, in the presence of defendant and his counsel, any of the tests or experiments testified to by their experts. They also repeatedly objected to tests, experiments, and apparatus and operations of defendant, unless an opportunity was offered complainants to repeat the experiments, and unless defendant furnished like materials therefor, and unless the apparatus were offered in evidence or access to them was given complainants. Save for some of defendant’s materials furnished complainant, it does not appear to what extent, if at all, defendant obviated these objections. Otherwise the consideration of the case might be affected by them. See Steel Co. Case, 185 U. S. 420, 22 Sup. Ct. 698, 46 L. Ed. 968.
A decree in accordance herewith, as demanded in the bill of complaint other than for treble damages, will be entered; an accounting to be had before the master.