Opinion by

The bill filed by Charles Drake, deceased, in which his executors are the substituted plaintiffs, is for an accounting by the defendants for coal mined under two leases. The prayers are also for a decree declaring the leases forfeited for conditions broken, for an injunction if they should not be declared forfeited, and for the ascertainment of damages alleged to have been sustained by reason of the caving in and falling of the surface of the demised lands, caused by the mining and removal by the defendants of the pillars of coal under the surface. The material facts, all of which were properly found by the learned chancellor below, appear in its opinion, made part of the reporter’s notes. From the decree which followed them and the legal conclusions based upon them both sides have appealed.

By the first lease, dated November 28, 1863, Drake leased to the defendants’ predecessors all the coal under seventy-eight acres of land in Lackawanna Township, then Luzerne (now Lackawanna) County, except the upper or Marcy vein, the lessees agreeing to pay an annual minimum rental of $500, for which they were permitted to remove five thousand tons of coal each year during the term of the lease, which was for ten years and for such other and further time as the lessees and their legal representatives should continue to pay the rent as named in the lease, unless the said term should sooner be ended by nonpayment of rent. For all coal mined in excess of five thousand tons a year the lessees were to pay ten cents per ton. The chief contention between the parties to this proceeding is as to the meaning or effect to *30be given to the words in the lease “miners’ weight to be the standard” of each ton of coal mined.

In Drake et al. v. Lacoe et al., 157 Pa. 17, we construed the words “miners’ weight,” used in the lease of November 28, 1863, to mean “such quantity of coal, slate and dirt, as was agreed upon between the operators and the miners to be sufficient to make a ton of prepared coal.” In 1863 a “miners’ weight” ton in the anthracite region, in which the Drake property is located, was a gross ton plus ten per cent., or 2,464 pounds, in the mine car. It was afterwards ■ increased, and while it has varied somewhat in different sections of the valley in which the leased premises are located, it has been 3,024 pounds in their vicinity since about the year 1870; but, however it may have so varied, “miners’ weight” ton has always been the weight of mine-run material which the miner must produce in-order to be paid for mining a ton of coal, the excess being a more or less arbitrary allowance against him for refuse and waste in the mine car content. During the period for Avhich an accounting is asked a “miners’ Aveight” ton has been 3,024 pounds, and upon that basis the defendants are directed by. the court below to account under the-first lease. The main complaint of the plaintiffs is that the accounting ought to be made on the basis of 2,464 pounds — a “miners’ weight” ton at the time of the execution of the lease of 1863. If the intention of the parties to that lease Avas that the then “miners’ weight” ton should be the unvarying standard during the whole term of the lease upon Avhich the royalties were to be paid, they readily could, and most naturally would, have fixed it in figures at 2,464 pounds, for they are presumed to have knOAvn that a “miners’ Aveight” ton —the amount of mine-run material which a miner must produce in order to be paid for mining a ton of coal— would vary from time to time with changes in the quality of the material obtained from the mine. “Miners’ weight,” as we define it in Drake et al. v. Lacoe et al., is not a fixed, unvarying quantity of mine-run material, *31but is such quantity of the same as operators and miners may from time to time agree as being necessary or sufficient to produce a ton of prepared coal. This varying standard was manifestly adopted by the lessor and lessees when they used the well-known trade term “miners’ weight” — the ton weight of material required to be mined as equivalent to a ton of prepared coal— and the learned court below properly held that the accounting must be on the basis of a “miners’ weight” ton as fixed and agreed upon by the operators and miners during the accounting period.

Nothing said in Drake et al. v. Lacoe et al. sustains the contention of the defendants that their liability is limited to prepared sizes of coal. The decree in that case related to the lease of 1865 of the upper vein, and what we said was that, as the plaintiffs and defendants had placed their own interpretation upon its terms, they were both bound by it.

We need add nothing to what was said by the court below as to the plaintiffs’ claim for pillar coal, and we concur in its conclusion that, under the evidence, they were ■hot entitled to an injunction to restrain further mining, nor to a decree declaring the leases forfeited.

Each appeal is dismissed at the costs of the appellants.