This is a suit in equity to enjoin the infringement of letters patent No. 319,125, issued June 2, 1885, to Rice, Steiger & Thurber, and letters patent Eo. 342,852, issued June 1, 1886, to Austin Walrath. Both patents are for processes in the preparation of material for asphalt payements, and laying and rolling the same. In both the material so to be prepared and laid is the natural bituminous rock of California, a substance composed, of sandstone and bitumen or asphaltum, commingled in such proportions as to require the addition of no other material for pavement purposes. So far as this suit is concerned, there is no discernible difference in the processes described in the two' patents. The earlier, or, as it is called, the Thurber, patent is clearly an anticipation of the Walrath patent, and it will be unnecessary to make further reference to the latter, as it conferred upon the complainant no right not acquired under the earlier patent. The claim of the Thurber patent is as follows:
“The xu'ocess of preparing roofing and paving material, consisting in the following steps: First, softening pure native asphaltum hy tliq application of hot water or steam thereto; and, secondly,• pressing it under heated rollers or other heated irons, substantially as and for the purpose set forth.”
It is admitted that the defendant has laid pavements under the process above described, and that he has infringed the same if the patent is held valid. The defenses relied upon are that the patent is void for want of novelty and invention, that the invention was made by only one of the three joint patentees, and that the description of the invention in the specification is not in such full, clear, concise, and exact terms as to enable any person skilled in the art to use the same.
It wil be observed that there are two distinct steps in the process as described — First, softening- the material by hot water or steam; second, rolling it with heated irons while still hot and perméated with moisture from the steam. It is in the immediate use of the material so softened and moistened that the invention which is involved in the process is said to consist. The other features of the process — the application of the steam and the use of the heated rollers — are undoubtedly old. The bituminous sandstone of California, which is the subject of this process, is a hard substance when quarried, and is required to be made soft and pliable before it is available for pavements. Prior to the experiments of Thurber and his associates with hot water and steam, it had been the practice to soften the rock either by dry-heating- the same in caldrons, or by cooking it with the addition of coal tar. The result was unsatisfactory, as the material was either burnt in the process, and thereby rendered porous and brittle, or, through the addition of the coal tar, -was left sticky and difficult to handle. The patentees of the Thurber process discovered that the use of hot water or steam directly applied to the bituminous rock, and without the addition of coal tar or any other substance, produced a better result, left the material in condition for immediate use for paving, and greatly simplified the preparation of the same. The Thurber patent has been twice sustained in this court, — in Rock Co. v. Walrath, 41 Fed. 883, *283and Pacific Contracting Co. v. Southern California, etc., Co., 48 Fed. 300. In the latter case the same defenses were made that are presented in the case now before the court. It was there held that, although the idea of the application of hot water or steam to a substance for the purpose of rendering it soft and pliable was undoubtedly old, yet that the idea of such apx>lication to bituminous rock in the course of preparation for roofing or paring purposes involved an element of invention from the fact that it was opposed to the generally accepted theory of the treatment of that substance, and the universal belief of. those engaged in using the same, which was that the material must be kept waterproof, and must only be heated by dry heat, to the rigid exclusion of moisture, and that the presence of water or steam tended to its disintegration and destruction. That decision will be <’ 'cisive of this case unless the evidence now offered presents the defenses in a new or different light.
The defendant insists that lie lias furnished new evidence of the want of invention in the Thurber patent in the fact that the same process was described and given to the public in the hook of E. Dietrich entitled “Die Asphalt Btrassen,” published in Berlin, in Germany, in the year 1882. Reference was made to the contents of that volume in the answer to Ihe bill, and it is now produced in evidence. It treats of the' construction of asphalt streets and roads. On page 23 is described the process of preparing the bituminous rock of Lobsann for transportation from the quarry and for use in street-making. The Lobsann bituminous rock is described as consisting of limestone unevenly impregnated with bitumen, with portions of the limestone wholly unimpregnated. One of Ihe objects of the process is the elimination of the unimpregnated rock. This is done by placing the crude rock in iron vessels, into which steam is forced. The steam causes the rock to fall to piece's, and the non-impregnated portions an* thrown out, while the remainder is ground be!ween rollers. The* author proceeds to say:
‘T>ut since flic material, in consequence of this steaming- process, is” so completely penetrated with moisture (which afterwards it does not lose in the immediately following process of crushing and grinding), and since the removal of this moisture is of groat importance as well in the manufacture of mastic as in the production of compressed asphalt, it might perhaps lx* preferahle to conduct hot air into the vessel of about- too deg. Celsius.”
On page 108 the exclusion of the moisture is further insisted upon:
“The expulsion of ihe natural moisture* from the asphalt stone is absolutely necessary, because the powder cannot he pressed into a, solid hody hy roller or press unless it be in a perfectly dry condition. Therefore bring up the temperature to the highest degree possible without running any danger of driving- the bitumen out with the water.”
In short, the process described by Dietrich consists in first steaming the rock, for the double purpose of separating (he unimpreg-nated portions of the rock from the remainder, and softening the latter for grinding, and, second, evaporating the moisture from tin* ground product to render it fit for compression into pavement. Tin* Thurber process consists in first softening the rock by steam, and, second, in coinpressing it into pavement while still hot, and permeated with moisture.
*284The question whether or not there is invention in the Thurber process is not perceived to be affected by any fact disclosed in the book of Mr. Dietrich. If the process described in that volume has any bearing upon the questions involved in this case, it is rather to emphasize the fact that the Thurber process ran counter to all the accepted ideas of the treatment of bituminous rock for pavement purposes, for Dietrich adheres to the view that all moisture must be excluded. Through the publication of his volume there was con-f structively brought to the knowledge of all the world the fact that bituminous rock could be and had been softened by the application of steam, and that such application was not deemed injurious provided the moisture so introduced was expelled before compressing and using the material. This was the state of the art prior to the invention of Thurber and his associates. What they added was the idea of the immediate use and compression of the steam-softened material into pavement without the expulsion of the moisture, or perhaps it would be more accurate to say they omitted from the Dietrich process a step which Dietrich and all others considered essential, namely, the evaporation of the moisture which had been introduced in the steaming process. Therein is the essence of the Thurber invention. It was not the discovery of the fact that bituminous rock may be softened by steam. That fact may be presumed to have been known from time immemorial. It was the discovery that the presence of the moisture in the substance thus treated did not tend to destroy and disintegrate the finished product, — the pavement. The complainant is entitled to a decree as prayed for;