There is some reason to apprehend that the patentee, in this case, failed to secure to himself all that he might have secured, if he had not restricted his claim, as the inventor, to a mere combination. The argument of the plaintiff's counsel assumes, that the combination of a spiral conductor with a water wheel open at the bottom, through which the water would fall freely after passing through ogee buckets constructed as described in the specification annexed to the patent, was his invention; and this assumption does find some color in the language of the specification. But the patentee made no such claim in fact. It is perfectly consistent with the specification, and with the plaintiff’s claim, to assume: (1) That the water-wheel described was not new; (2) that the spiral conductor was not new; (3) that the use of a tube. F, above a waterwheel, to remove water which, being thereon, would impede its revolutions, was not new; (4) that the use of the spiral conductor described, to conduct water to the periphery of just such a wheel, and cast it against the buckets, was already common. The patentee may have invented each, but he has not said so, and he has not claimed that he did.
An inventor must be taken to know of what his invention consists, and his patent does not secure to him the exclusive right in anything more than he claims to have invented. If his specification is imperfect, through mistake or inadvertence, the law enables him to obtain a reissue, so as to conform to the truth in this respect.
Here, the patentee has narrowed his claim, by the use of terms which are express and clear: “What I claim as my invention, and desire to secure by letters patent, is, the combination of the wheel, constructed as herein before described, with the spiral conductor D, and tube F, so as to get the full pressure of the water, while the wheel is relieved of its *672weight, in the manner and for the purpose set forth.” He does not claim to have invented either of the parts separately, aor to have invented a useful combination of any two of the parts without the third. He may have invented each of them, but he has not obtained a patent for either of them. We are, therefore, left to the assumption, that each was old, and that his specific combination alone was new.
It is quite true, that, in the construction of a claim, reference is to be had to the descriptive portion of the specification, or to any other portion of it, to ascertain the true interpretation of the claim. But, where the claim is such as to leave no room for construction, where it is clear and explicit, and, especially, where there is nothing in the specification which shows that the patentee did not mean just what the plain language of the claim imports, we are not aided by, and have no need of aid from, such specification.
The case, therefore, stands thus: The pat-entee has not claimed to have invented the wheel described, or the combination of the wheel with the spiral conductor, and has not obtained a patent for either. He, therefore, has no exclusive right by virtue of which he could prevent the defendant’s using either.
It is true, that inventions in general involve combinations of old devices. No machine is made that does not, in various of its parts, require, for its construction, the use of what is known and open to the use of all the world. Hence, when a machine is patented as an aggregate, third parties may not deny an infringement on the ground that they omit immaterial parts, or use fewer of the original old elements, or substitute equivalents. The question will still recur — Is the alleged infringement substantially the same machine?
But, here, the patentee claims to combine a wheel and a spiral conductor, neither of which he claims to have invented, with a tube, F, to carry off the water from the surface of the wheel. Now, if the defendant had substituted an equivalent device for the tube P, he might be an infringer. But he was not, by this patent, prevented from using the other two without any such device. His using them in a location, in reference to the flume, which rendered the tube unnecessary and useless, was not substituting an equivalent device, but was only using them without any device of any kind for the purpose indicated. The case falls, therefore, within the rule stated, namely, that, when a combination of known elements or devices is patented, and the combination only, the use of any of the devices less than all is no infringement This rule is not to be construed so strictly as to conflict with the other rule above stated, and to permit the substitution of equivalent devices, where the combination is substantially the same. But, here, the tube P is a distinct member of the combination, for a specific useful purpose; and it cannot be rejected in determining what is, in law and in fact, the subject of the patent.
If the wheel had been claimed, or the combination of the wheel and the spiral con-duetor, the defendant could not have protected himself by dispensing with the tube P, although the plaintiff had also patented the three in combination; but, as the case stands, I see no alternative but to hold the ruling on the trial correct.
The motion for a new trial is denied.