Opinion of the Court.

in this case. Without going at length into the subject, it may be safely said that by the weight of authority, as well as the preponderance of opinion, it is the general rule of American law that a grant will be presumed upon proof of an adverse, exclusive, and uninterrupted possession for twenty years, and that such rule will be applied as a presumptio juris et de jure, wherever, by possibility, a right may be acquired in any manner known to the law. 1 Greenleaf Ev. 12th ed. § 17; Ricard v. Williams, 7 Wheat. 59, 109; Coolidge v. Learned, 8 Pick. 503.

Nothing, it is true, can be claimed by prescription which owes its origin to, and can only be had by, matter of record; but lapse of time accompanied by acts done, or other circuinstances, may warrant the jury in presuming a grant or title by record. Thus, also, though lapse of time does not, of itself, furnish a conclusive bar to the title of the sovereign, agreeably to the maxim, nullum tempus occurrit regi; yet, if the adverse claim could have a legal commencement, juries are advised or instructed to presume such commencement, after many years of uninterrupted possession or enjoyment. Accordingly, royal grants have been thus found by the jury, after an indefinitely long-continued peaceful enjoyment, accompanied by the usual acts of ownership. 1 Greenl. Ev. § 45.

The principle upon which this doctrine rests is one of general jurisprudence, and is recognized in the Roman law and the codes founded thereon, Best's Principles of Evidence, § 366, and was, therefore, a feature of the Mexican law at the time of the cession.

Finally, the rule of the law of nations, that private property in territory ceded by one nation to another, when held by a title vested before the act of cession, should be respected; the express provisions to that effect contained in the treaty between Mexico and the United States; the evidence of the fact of a grant, legal under the forms of Mexican law, and of a juridical possession given thereunder, and the strong presumption growing out of an exclusive and uninterrupted possession and enjoyment of more than half a century, bring us to concur in the decree of the court below.

Statement of the Case.

The objection that the Atlantic and Pacific Railroad Company, as grantee from the United States, of a part of the tract in question, was a necessary party defendant, has not been pressed in argument, and we only notice it to say that, under the provisions of the fifth section of this act, the private rights of third parties are not affected by any proceeding or decree under said act.

The decree of the court below is

Affirmed.

THE INCANDESCENT LAMP PATENT.1

APPEAL FROM THE CIRCUIT COURT OF THE UNITED STATES FOR THE WESTERN DISTRICT OF PENNSYLVANIA.

No. 19. Argued October 29, 30, 1894. -Decided November 11, 1895.

With the exception of the third claim, viz., for "the incandescing conductor for an electric lamp, formed of carbonized paper, substantially as described," the claims in the letters patent No. 317,076, issued May 12, 1885, to the Electro-Dynamic Light Company, assignee of Sawyer and Man, for an electric light, are too indefinite to be the subject of a valid monopoly.

THIS was a bill in equity, filed by the consolidated Electric Light Company against the McKeesport Light Company, to recover damages for the infringement of letters patent No. 317,076, issued May 12, 1885, to the Electro-Dynamic Light Company, assignee of Sawyer and Man, for an electric light. The defendants justified under certain patents to Thomas A. Edison, particularly No. 223,898, issued January 27, 1880; denied the novelty and utility of the complainants' patent, and averred that the same had been fraudulently and illegally procured. The real defendant was the Edison Electric Light Company, and the case involved a contest between what are known as the Sawyer and Man and the Edison systems of electric lighting.

This is the title of this case in the opinion of the court; but its docket title is, "The Consolidated Electric Light Company, Appellant, v. The McKeesport Light Company."

VOL. CLIX-30

Statement of the Case.

In their application, Sawyer and Man stated that their invention related to "that class of electric lamps employing an incandescent conductor enclosed in a transparent, hermetically-sealed vessel or chainber, from which oxygen is excluded, and more especially to the incandescing conductor, its substance, its form, and its combination with the other elements composing the lamp. Its object is to secure a cheap and effective apparatus; and our improvement consists, first, of the combination, in a lamp chamber, composed wholly of glass, as described in patent No. 205,144," upon which this patent was declared to be an improvement, "of an incandescing conductor of carbon made from a vegetable fibrous material, in contradistinction to a similar conductor made from mineral or gas carbon, and also in the form of such conductor so made from such vegetable carbon, and combined in the lighting circuit with the exhausted chamber of the lamp." The following drawings exhibit the substance of the inven tion:

Statement of the Case.

The specification further stated that:

"In the practice of our invention we have made use of carbonized paper, and also wood carbon. We have also used such conductors or burners of various shapes, such as pieces with their lower ends secured to their respective supports, and having their upper ends united so as to form an inverted V-shaped burner. We have also used conductors of varying contoursthat is, with rectangular bends instead of curvilinear ones; but we prefer the arch shape."

"No especial description of making the illuminating carbon conductors, described in this specification and making the subject-matter of this improvement, is thought necessary, as any of the ordinary methods of forming the material to be carbonized to the desired shape and size, and carbonizing it while confined in retorts in powdered carbon, substantially according to the methods in practice before the date of this improvement, may be adopted in the practice thereof by any one skilled in the arts appertaining to the making of carbons for electric lighting or for other use in the arts."

"An important practical advantage which is secured by the arch form of incandescing carbon is that it permits the carbon to expand and contract under the varying temperatures to which it is subjected when the electric current is turned on or off without altering the position of its fixed terminals. Thus the necessity for a special mechanical device to compensate for the expansion and contraction which has heretofore been necessary is entirely dispensed with, and thus the lamp is materially simplified in its construction. Another advantage of the arch form is that the shadow cast by such burners is less than that produced by other forms of burners when fitted with the necessary devices to support them."

"Another important advantage resulting from our construction of the lamp results from the fact that the wall forming the chamber of the lamp through which the electrodes pass to the interior of the lamp is made wholly of glass, by which all danger of oxidation, leakage, or short circuiting is avoided." "The advantages resulting from the manufacture of the carbon from vegetable fibrous or textile material instead of

Statement of the Case.

mineral or gas carbon are many. Among them may be mentioned the convenience afforded for cutting and making the conductor in the desired form and size, the purity and equality of the carbon obtained, its susceptibility to tempering, both as to hardness and resistance, and its toughness and durability. We have used such burners in closed or hermetically-sealed transparent chambers, in a vacuum, in nitrogen gas, and in hydrogen gas; but we have obtained the best results in a vacuum, or an attenuated atmosphere of nitrogen gas, the great desideratum being to exclude oxygen or other gases capable of combining with carbon at high temperatures from the incandescing chamber as is well understood."

The claims were as follows:

"1. An incandescing conductor for an electric lamp, of carbonized fibrous or textile material and of an arch or horseshoe shape, substantially as herein before set forth."

"2. The combination, substantially as herein before set forth, of an electric circuit and an incandescing conductor of carbonized fibrous material, included in and forming part of said circuit, and a transparent hermetically sealed chamber in which the conductor is enclosed."

"3. The incandescing conductor for an electric lamp, formed of carbonized paper, substantially as described."

"4. An incandescing electric lamp consists of the following elements in combination: first, an illuminating chamber made wholly of glass hermetically-sealed, and out of which all carbon-consuming gas has been exhausted or driven; second, an electric-circuit conductor passing through the glass wall of said chamber and hermetically sealed therein, as described; third, an illuminating conductor in said circuit, and forming part thereof within said chamber, consisting of carbon made from a fibrous or textile material, having the form of an arch or loop, substantially as described, for the purpose specified."

The commercial Edison lamp used by the appellee, and which is illustrated below, is composed of a burner, A, made of carbonized bamboo of a peculiar quality discovered by Mr. Edison to be highly useful for the purpose, and having a length of about six inches, a diameter of about five one thou