by John Marshall Harlan

“ At all events, the decisions of this court are numerous that the laws which prescribe the mode of enforcing a contract, which are in existence when it is made, are so far a part of the contract that no changes in these laws which seriously interfere with that enforcement are valid, because they impair its obligation, within the meaning of the Constitution of the United States. ”

“ This is especially true with regard to the law of real estate and the construction of state constitutions and statutes. Such established rules are always regarded by the Federal courts, no less than by the state courts themselves, as authoritative declarations of what the law is. But where the law has not been thus settled, it is the right and duty of the Federal courts to exercise their own judgment; as they also always do in reference to the doctrines of commercial law and general jurisprudence. ”

“ Where a deed conveys the coal under a tract of land, together with the right to enter upon and under said land, and to mine, excavate, and remove all of it, there is no implied reservation in such an instrument that the grantee must leave enough coal to support the surface in its original position. 4. It is the duty of the court to construe contracts as they are made by the parties thereto, and to give full force and effect to the language used, when it is clear, plain, simple, and unambiguous. ”

“ But it does issue, and has been recognized by this court as issuing, from the state courts as well as from the state legislatures. When we know what the source of the law has said that it shall be, our authority is at an end. The law of a state does not become something outside of the state court, and independent of it, by being called the common law. ”

“ There is no room for doubt as to the scope of the decision in the Griffin Case. The syllabus-which, in West Virginia, is the law of the case, whatever may be the reasoning employed in the opinion of the court-is as follows: '1. Deeds conveying coal with rights of removal should be construed in the same way as other written instruments, and the intention of the parties, as manifest by the language used in the deed itself, should govern. ”

“ Co. must not be interpreted as applicable to a case like the one before us, nor as denying the authority and duty of the Federal court, when determining the effect of conveyances or written instruments between private parties, citizens of different states, to exercise its own independent judgment where no authoritative state decision had been rendered by the state court before the rights of the parties accrued and became fixed. ”

“ Since the ordinary administration of the law is carried on by the state courts, it necessarily happens that by the course of their decisions certain rules are established which become rules of property and action in the state, and have all the effect of law, and which it would be wrong to disturb. ”

“ Co., one of the cases cited, was a suit in the Federal circuit court to foreclose a mortgage on real estate. A foreclosure and sale were had, and the decree, following the established rules of the Federal court, allowed the defendant to pay the mortgage debt in one hundred days; and if the debt was not paid within that time, then the master was ordered to sell the land for cash, in accordance with the course and practice of the Federal court. ”

“ But the decision of the state court, as to the constitutionality of the statute in question, having been rendered after the rights of parties to this suit had been fixed by their contracts, the circuit court would have been derelict in duty if it had not exercised its independent judgment touching the validity of the statute here in question. ”

“ The question here involved as to the scope and effect of the writing given by Kuhn to Camden does not depend upon any statute of West Virginia, nor upon any rule established by a course of decisions made before the rights of parties accrued. So that the words above quoted from East Central Eureka Min. Co. ”