Statement of the Case.

judgment of the Circuit Court on other grounds. 127 U. S. 1, 45.

On March 6, 1889, the parties, by another stipulation in writing, agreed that the previous judgment of the Circuit Court in the present case be set aside, and the case submitted to the Circuit Court upon an agreed statement of facts, "on which findings shall be made and conclusions of law drawn by the court."

On September 6, 1889, the Circuit Court, pursuant to this stipulation, ordered its former judgment to be set aside, and made and filed findings of fact in accordance with the agreed

statement.

By these findings of facts, it appeared that, before and at the time of the assessment of these taxes, the defendant owed a debt secured by mortgage of its railroad, its franchise and its rolling stock and appurtenances, to the amount of more than $3000 a mile; that the State Board of Equalization valued and assessed the defendant's franchise, roadway, roadbed, rails and rolling stock, not separately, but together, (and not including any other kind of property,) at their full value, without deducting the value of the mortgage or any part thereof, although knowing of its existence, and did not deem or treat the mortgage as an interest in the property, and assessed the whole value of the property to the defendant as if there had been no mortgage thereon, but made the assessment upon the same basis for valuation as all other property in the State was valued for the purpose of taxation; and that there were at that time divers railroads in the State, owned and operated by corporations other than railroad corporations, and by individuals and partnerships.

Upon the facts found, the Circuit Court concluded, as matter of law, that the defendant was entitled to judgment. Judgment was entered accordingly, and the State of California sued out this writ of error.

The Attorney General of the State admitted in his brief, and, when this case was called for argument, stated in open court, the following fact:

"In the year 1893, the defendant offered and tendered to

Mr. William H. H. Hart, for the State of California.

the plaintiff a sum of money equal to the taxes, penalties, interest and attorney's fee, to recover which this action was brought, and costs of suit, which offer and tender have not been accepted; but the money has been deposited by the defendant in bank, in accordance with the provisions of section 1500 of the Civil Code of California, which reads as follows: 'An obligation for the payment of money is extinguished by a due offer of payment, if the amount is immediately deposited in the name of the creditor, with some bank of deposit within this State of good repute, and notice thereof is given to the creditor.""

Mr. William H. H. Hart, Attorney General for the State of California, after stating the fact of the offer and deposit of money as aforesaid, said:

I respectfully submit that this offer should not prevent the hearing of this cause and a decision of the constitutional question involved.

There are other cases depending upon the determination of this. It will be seen in the record, that there was a stipulation in this case, and three others, that the decision that might be made in this court in the case of The People of the State of California v. The Central Pacific Railroad Co., should be treated as a decision in all of the cases, provided the decision should be upon points involved therein, and if not so made, then the judgment of the Circuit Court in any of these cases should be set aside and findings of fact therein made. That case having been decided against the State because the assessment included steamboats and federal franchise, (see 127 U. S. 1,) and the question made in the present case under the Fourteenth Amendment not having been passed upon, counsel of the parties signed a stipulation to have the judgment set aside in this case, and to submit the same to the Circuit Court upon the facts stated in the stipulation, and it was accordingly thus submitted and decided by the Circuit Court, the design of the stipulation thus submitting the case being to obtain a decision which would also dispose of the remaining two cases embraced

Opinion of the Court.

in the stipulation first made, that stipulation having been made to carry out the design of the first, that is, to obtain a decision that will dispose of all these cases.

Therefore, nothing short of a payment of what is claimed in those two cases, as well as in this, should be regarded as dispensing with a decision of the constitutional question raised in this case, and which is the same in the three cases.

It is of the utmost importance to the people of the State of California, that it be determined whether an assessment of the property of railroad corporations in the manner required by the constitution of California is valid, so it may be known, when these assessments are made, whether they can be included in the sources of revenue that can be relied upon in the administration of the government of that State, or whether such corporations are at liberty to decline to pay taxes, and to pay only what sums and when they may choose, merely as voluntary contributions to the public funds of California.

The court declined to hear further argument.

Mr. George A. Johnson, a former Attorney General of the State of California, and Mr. Samuel Shellabarger and Mr. Jeremiah M. Wilson also submitted briefs for the plaintiff in error.

Mr. George F. Edmunds, Mr. Harvey S. Brown and Mr. Creed Haymond submitted briefs on the merits for the defendant in error.

Mr. Harvey S. Brown also submitted a brief on a motion to dismiss the writ of error.

MR. JUSTICE GRAY delivered the opinion of the court.

Upon the fact most properly and frankly admitted in open court by the Attorney General of the State of California, there can be no doubt that this writ of error must be dismissed, because the cause of action has ceased to exist. Any obligation of the defendant to pay to the State the sums sued for in this case, together with interest, penalties and costs, has been

Opinion of the Court.

extinguished by the offer to pay all these sums, and the deposit of the money in a bank, which by a statute of the State have the same effect as actual payment and receipt of the money. And the State has obtained everything that it could recover in this case by a judgment of this court in its favor. The duty of this court, as of every judicial tribunal, is limited to determining rights of persons or of property, which are actually controverted in the particular case before it. When, in determining such rights, it becomes necessary to give an opinion upon a question of law, that opinion may have weight as a precedent for future decisions. But the court is not empowered to decide moot questions or abstract propositions, or to declare, for the government of future cases, principles or rules of law which cannot affect the result as to the thing in issue in the case before it. No stipulation of parties or counsel, whether in the case before the court or in any other case, can enlarge the power, or affect the duty, of the court in this regard.

The case at bar cannot be distinguished in principle from previous cases in which writs of error have been dismissed by this court under similar or analogous circumstances. Lord v. Veazie, 8 How. 251, 255; Cleveland v. Chamberlain, 1 Black, 419; Wood Paper Co. v. Heft, 8 Wall. 333; San Mateo County v. Southern Pacific Railroad, 116 U. S. 138; Little v. Bowers, 134 U. S. 547; Singer Manuf. Co. v. Wright, 141 U. S. 696. See also Elgin v. Marshall, 106 U. S. 578.

Writ of error dismissed.

Statement of the Case.

DALZELL v. DUEBER WATCH CASE MANUFACTURING COMPANY.

SAME v. SAME.

APPEAL FROM THE CIRCUIT COURT OF THE UNITED STATES FOR THE SOUTHERN DISTRICT OF NEW YORK.

Nos. 213, 214. Argued April 18, 19, 1893. - Decided May 10, 1893.

An oral agreement for the sale and assignment of the right to obtain a patent for an invention is not within the statute of frauds, nor within section 4898 of the Revised Statutes requiring assignments of patents to be in writing; and may be specifically enforced in equity, upon sufficient proof thereof.

A manufacturing corporation, which has employed a skilled workman, for a stated compensation, to take charge of its works, and to devote his time and services to devising and making improvements in articles there manufactured, is not entitled to a conveyance of patents obtained for inventions made by him while so employed, in the absence of express agreement to that effect.

Specific performance will not be decreed in equity, without clear and satisfactory proof of the contract set forth in the bill.

Where, at the hearing in equity upon a plea and a general replication, the plea, as pleaded, is not supported by the testimony, it must be overruled, and the defendant ordered to answer the bill.

THESE were two bills in equity, heard together in the Circuit Court, and argued together in this court.

On March 31, 1886, Allen C. Dalzell, a citizen of the State of New York, and the Fahys Watch Case Company, a New York corporation, filed a bill in equity against the Dueber Watch Case Manufacturing Company, a corporation of Ohio, for the infringement of two patents for improvements in apparatus for making cores for watch cases, granted to Dalzell, October 27, 1885, for the term of which he had, on January 21, 1886, granted a license, exclusive for three years, to the Fahys Company.

To that bill the Dueber Company, on June 4, 1886, filed the following plea: "That prior to the grant of the said