The opinion
KOHLSAAT, Circuit Judge
(concurring). Kraut in 1869 found that Von Gilm’s so-called acetyl salicylic acid of 1859, obtained by treating the acids with acetyl chloride, and purified by recrystallizing from boiling water, responded to the same tests as Gerhardt’s product resulting from the action of chloracetyl on sodium salicylate, extracted with ether and recrystallized from boiling water. He also found that the mass so produced was easily dissolved in wine spirits, ether, and benzole, viz., these are given as purifying substances. Hoffmann provides for a mixture of salicylic acid and acetic anhydride subjected to heat. It does not appear that the mass so produced differs from those described by Kraut. Hoffmann then presses out the anhydride and recrystallizes from dry chloroform. His claim for novelty over the Kraut, Gilm, and Gerhardt products, is based upon the fact, as claimed, that his result responds to certain tests, to which the others do not purport to respond, and that the others give certain features which disclose impurity, and masses entirely different from his.
Hoffmann fixes his solidifying point at 70 degrees Centigrade; while Kraut fixes his at 118 degrees to 118.5 Centigrade.
*706 The evidence favors the Kraut figure, and Hoffmann is not sure enough of his to include it in his tests. Kraut, as was the custom in 1869, fails to give any melting point. Hoffmann, in 1898, fixes the melting point of his product at 135 Centigrade, which element he enumerates as one of his tests. He also states that his new body, when boiled with water, is readily split up, acetic and salicylic acid being produced, and quotes Kraut as saying that if the Kraut product be boiled even for a long time with water, acetic acid is not produced. What Kraut did in fact say is that:
“They dissolve very little in cold water, melt on heating with water, to an oil, which, even with prolonged boiling with water, allows no acetic acid to escape and suffers no noticeable decomposition at 'all.”
The grammatical arrangement of this statement seems to be somewhat involved. The word “they” may refer to the products or bodies produced by his two methods, or it may refer to the white needles. The word “which” would seem to apply to the oil produced by boiling the mass, though complainant and Prof. Haines seem to apply it to the two bodies being dealt with. The latter construction se'ems strained, in view of the fact that it is used in connection with the singular verbs “allows” and “suffers.”
Kraut says that his aqueous solution colors iron chlorid like salicylic acid. This defendant insists must refer to the solution accompanying the oil resulting from heating with water. It is difficult to account for this on any other ground than that Kraut’s product, when boiled with water does decompose and produce acetic acid. At any rate, so defendant asserts, Hoffmann is not justified in his statement that Kraut says acetic acid is not produced by boiling his product for a long time with water, since what Kraut in fact says is that the oil produced by prolonged boiling with water, does not throw off acetic acid or appreciably decompose. Each of the three masses dealt with by Kraut and Hoffmann, it appears from the record, does give out, on boiling with water, an oil which is “settled off.” Kraut distinctly does not say, defendant insists, that acetic acid is not produced in the course of the treatment of his product as above. This seems to be the reasonable import of his language.
Notwithstanding the foregoing, defendant’s witness Haines (page 116 of record) says:
“In regard to two points, Kraut’s description of acetyl salicylic acid is somewhat misleading. The first of these is in regard to the effect of boiling water on the compound. He describes with perfect accuracy what he undoubtedly observed, viz., that in boiling the acid with water, it suffers no noticeable decomposition and allows no acetic acid to escape, although, as a matter of fact, it is slowly decomposed by hot water. This decomposition, however, is easily overlooked. If a little of the perfectly pure acid is boiled with water, no decomposition is seen by the unaided eye, and there is no odor of escaping acetic acid unless a. considerable amount of material is acted on, and even then the odor might be easily overlooked, if one’s sense of smell was not naturally acute, or if one was suffering from a little catarrhal cold. * * * The second point in Kraut’s description of acetyl salicylic acid which is somewhat misleading is his statement that its aqueous solution strikes a color with iron chloride like that produced with salicylic acid. * * * It was the presence in Kraut’s product of a little free salicylic acid, either orig *707 Inally present or developed by dissolving in hot water, or both, that undoubtedly misled him.”
Inasmuch as response to tests seems to be a fair method of determining the lack of identity of the product of the patent in suit with Kraut’s product, it becomes important that the results of the tests should correspond in all material respects. If the construction placed upon Kraut’s language by defendant’s expert is to prevail over what might seem to be the unskilled judgment of counsel and court in that respect, it follows that the language of the patent in suit with reference to Kraut’s article is justified, and that, failing to meet these material tests, the latter cannot be said to correspond to Hoffmann’s product. Thus, while Kraut seems to have pointed out the method of obtaining a practically pure acetyl salicylic acid by the boiling water process, giving ether,- wine spirits, and benzole as solvents — that is, dry solvents — it appears that in two important respects his language is misleading. It is evident that he was not principally concerned with obtaining the pure article, nor with anticipating Hoffmann’s tests. He does not give a process which can be said to lead one skilled in the art to the product of Hoffmann, if his language is to be followed literally. Something has to be supplied before Kraut’s product can be deemed to meet Hoffmann’s decomposition test. That the crystal needles in both cases, Kraut’s and Hoffmann’s, are practically the same, differing, if at all, in degree of purity, admits of little doubt.
The record discloses attempts to demonstrate their actual identity, but these are not produced in such shape as to avail the appellant. Courts place little weight on ex parte demonstrations in any case,but especially is this true with regard to experiments with chemicals. Speaking therapeutically, it is of course desirable that the acetyl salicylic acid be pure; that is, substantially so. Aspirin is nothing more than this. So long as there is no appreciable amount of free salicylic acid in the product, the beneficial effects of salicylic acid are preserved. Had Kraut produced pure acetyl salicylic acid, he would have anticipated aspirin — no matter by what name it is called. The evidence is that a substantially pure article will suffice. Kraut claims to have produced a 98 per cent, article, according to his baryta titration test. The efficiency of this test is disputed. It may be conceded therapeutically that purity is a patentable advance over practical purity, but it is a very narrow advance. Acetyl salicylic acid, obtained by Kraut’s process — -that is, the article produced by water, or the ether, benzole, or wine spirits crystallization — belongs to the public, whether pure or only approximately so; and, had appellant shown that he was employing these methods, he could not have been held to infringe. On the contrary, the tests called for by the patent apply to defendant’s product and do not apply to Kraut’s. It surely was within appellant’s power to rebut the presumption arising from these facts, had the Kraut processes been employed by him, but no attempt has been made to do so. There would seem to be in this a suggestion that the process rather than the product should have been claimed. Whatever this leads to, it still is true that so far as the record shows, Hoffmann’s product is different from Kraut’s, and there *708 fore not anticipated or in the possession of the public prior to the filing of his application.
For these reasons, I concur in the conclusion of the majority of the court.