opinion: L. HAND, Circuit Judge
  (after stating the facts as above). However anomalous may be a bill of review, or a bill in the nature of a bill of review, before final decree, we are content to accept this one as the equivalent of a petition for rehearing upon new evidence. Even so, the proceedings were quite irregular. The motion should have been granted, the first decree vacated, the new proofs taken and a now decree entered, if we are to have jurisdiction. Strictly speaking nothing of the sort was done, hut the first decree was made the decree on the bill. However, the affidavits were considered along with the old proof and it seems to us that, however defective the form, in substance the decree appealed from is a new decree, entered upon all the evidence, old and new, and the only interlocutor}’ decree now outstanding in the case, Armat, etc., Co. v. Edison Mfg. Co. (C. C. A. 2), 125 F. 939. In spite of the formal irregularity of what took place, the substance is such as gives us jurisdiction of the controversy.
  The only attack upon the validity of Getts’ patent worthy the name is from the “Detroit switch” and the “Cartwright switch.” . The “Detroit switch” did not have two blades, held together by a bolt and held apart by a spacing block between their outer ends. It is true that in operation this switch did clamp the two blades against the clip, just as Getts’ switch did; but the two blades could move together only through the two bolts one on either side of the clip. Moreover, as the blades had to bo free to approach or recede, they could not be solidly fastened together by the bolts; they must “float.” This was an essential feature of the structure, if it was to operate like Getts. It necessarily resulted from this design that, when the switch was pulled down upon the terminal, tho longer arm must pull down the shorter only by means of the two bolts that connected them. This tended to twist the two out of alignment, and the plaintiff asserts that it made the switch short-lived and interfered with the contact. To, this assertion we need not assent, for it is quite enough that the mode of operation and the structure differed, and that these differences resulted in the entire elimination of tho older type, and the substitution of the patented disclosure.
  The Cartwright switch is even more foreign to the patent. Here there was nothing at all which automatically pressed the floating blades upon the clip. On the contrary, after the switch had been closed, the blades were in loose contact, and had to be pressed against the clip by a lever operating by a screw thread and two springs. It is apparent that this has nothing whatever to do with Getts’ patent. Thus there is no valid anticipation.
  The defendant’s argument on the issue of infringement is that the blades of its switch do not in fact move to and from the spacing block, but that, on the contrary, they exert pressure upon the terminal only by their own resiliency, as in tho early two-bladed switches. It is a complete answer to this that the defendant’s own witness, Henke, acknowledged that there was a total movement of about a fifty-third of an inch. The play in the plaintiff’s practice is only one thirty-second of an inch, and infringement is not avoided by decreasing the amount, if the operation remains the same. We are not impressed by the attempt to turn this difference in degree into one of kind. If the defendant wishes to lock the ends of the blades to the spacing block so tightly that they will not move at all, it is easy to do so, and it will escape the injunction. While the bolt head is not in close contact with both blades when the switch is raised, that proves nothing. The important action is the movement to and fro of tho blades with respect to each other, and with the proof of this was proved the issue of infringement.
  Of the two classes of claims contained in the Jacobs patent, the latch and the clamping springs, the validity of the first alone is challenged. The nearest approach by way of anticipation is Defendant’s Exhibit 2, which was sold and installed both at St Louis and at Detroit. If it had worked successfully, perhaps it would have boon a good anticipation; at least, we shall assume as much. So far as we can see, the only difference between it and Jacobs’ disclosure is that the head of the latch has lugs of slighter strength than the solid T-end disclosed in tho patent, and this is not a feature of any of the claims.
  However, it is undisputed that all of these switches were unsatisfactory in operation, were taken out by the buyers, and were succeeded by the switch of the patent. Just what tho trouble was does not appear with entire certainty, though it is clear from Jacobs’ cross-examination that the lugs were not strong enough and broke in service. What were the, other difficulties, if any, is left wholly to speculation. The rule is that the defendant has the burden of proving that the alleged prior use was of an operable machine, for neither a prior patent nor a prior use is a good anticipation, if it is inoperable. Keystone Mfg. Co. v. Adams, 151 U. S. 139, 145, 14 S. Ct. 295, 38 L. Ed. 103; Kirchberger v. Amer., etc., Co. (C. C. A. 2) 128 F. 599, 605. We can see no difference between inoperability due to defective design-mg, by which the parts will not from the outset co-operate together at all, and that due to weak parts, which will break down in service. Nor do we think that a machine which breaks down under service is within the rule that an anticipation need not work as well as the patent. It will not do the work intended at all, because that is not confined to the initial movements.
  However, if the correction is obvious to the ordinary mechanic, the defect cannot be vital. In the case of a prior patent the claims would still be valid, if the correction was at once' apparent; a mere mistake in the disclosure is not fatal. Yet, if such a patent would be valid, it can only be because the public gets a good consideration for the monopoly, which means that, despite its defects, it contributes to the art. The same rule must apply to prior uses. Hence we conclude that, since the switches, Exhibit No. 2, were actually sold, not as experiments, but for commercial use, the fact that they were unsuccessful, because of an immediately remediable defect, would be irrelevant; they would still be anticipations.
  So the question is whether the defendant has shown that the defects were of a kind to be corrected without invention. It seems to us that the evidence does not justify that conclusion. The plaintiff was well skilled in the art; it had already been working for seven years upon the general subject of “disconnect” switches, and had tried two earlier forms; Exhibit No. 2 was the third. It is apparent that the problems involved were not easy, and that structures thought adequate by competent persons turned bad. The buyers were themselves engaged in electrical development; presumably they had the competence of the ordinary artisan, and, indeed, much more. They did'not themselves make the necessary changes, and, so far as appears, they did not suggest them. Jacobs, a new mind in this branch of the art, took the last step, and converted failure into success, and that a substantial success. In the light of the f oregoing, we should have to substitute our own uninformed speculation for the history of the art. We are, indeed, well aware of the hazards of such inferences; but, when all is said, in such cases there is nothing more reliable at hand. We can only resort to trite convention, and repeat that, if the change was so apparent, it should have earlier appeared.'
  The other alleged anticipation is the Detroit switch. The lateh was not of the Jacobs form; less like it, indeed, than Exhibit No. 2; and the member which operated it did not extend beyond the ends of the blades, being housed in the block attached to the longer. Verbally, at any rate, it does not read upon claims 1, 2, and 3. The difference is a slight one, as we have said; but the Detroit switch was inherently defective, and never got any currency. The member which operated the lateh lay loosely in the block, and was also housed in it. The aperture, being in the body of the housing, admitted of only a small play for the member, and was too small, if the blades were narrow. These were substantial defects, or, if not, substantial differences between the two. Not until after it had passed through the intermediate form of Exhibit No. 2 did invention come to an equilibrium. Again we say that it would be mere assumption to suppose that no invention was necessary to skip that step and to reach the desired f orm.
  The prior patents add nothing closer than what we have discussed, and there remains only the question of infringement. As to the claims for the lateh, no point is made; but claims 7, 35, and 38, involving the spring compression feature, are in issue. It is enough for these to say that, though the means is modified, it is in substance the same as is the result. The pressure in the alleged infringement is not confined to a geometrical line perpendicular to the blades. Eather it is an area of pressure, more or less broad on either side of the clip, forcing the blades together through the bearing of the springs upon the both heads. This is an equivalent of the claims whether or not it is an improvement.
  There were 9 claims in Getts’ patent and 39 in Jacobs’, of which all of the first and 27 of the second were here put in suit. Getts’ claims are not divided into classes determined by separate features of the disclosure; Jacobs’ were, as we have said. It was altogether unnecessary to cumber the ease with the mass of verbiage which these claims present in the aggregate. We have long enough protested against the practice; our complaints still l'emain unattended, and will be so until we take some action actively to discourage it. We mean to do so. Among several claims, the most general, which covers the alleged infringements, alone is necessary to a decision of the controversy; the rest there-' after necessarily present moot issues. If the defendant infringes the more general, a fortiori he infringes the particular. The plaintiff alleges that he has committed a tort in selling the device contrary to his monopoly. We so decide. He asks an injunction; we give it. Whether he has committed other torts is of no consequence. The dialectic which picks its way through the tangled language of 21 abstract statements of the same concept is barren and idle. We decline to engage in it.
  Wo hold claim 1 of the Getts patent, and claims 1 and 7 of the Jacobs patent, valid and infringed, and direct an injunction to go on each. We direct that the decree be modified, by dismissing the bill as to the other claims in suit without prejudice. The appellee will take no costs of the appeal for this reason.
  Decree modified as above, and, as modified, affirmed.