Opinion by
Mr. Justice Horace Stern,The adjudication of this controversy depends on the proper interpretation of the language reserving mineral rights in a deed of conveyance of a tract of land from William Rawle et al. to Jacob S. Young et al. dated August 28, 1855. The deed in question contained the following provisions: . the said parties of the first part hereto [the grantors] do hereby reserve to themselves their heirs executors administrators and assigns forever the full entire complete and exclusive ownership and right as though the present conveyance had not been made to all metals ores minerals coal mine-banks and deposits of ores minerals metals or coal which are or may be in or upon or which may at any time be discovered in or upon any part of the hereinbefore bargained and sold land and premises. And the said parties of the first part hereto do hereby reserve forever the full free absolute and exclusive right and authority for themselves their heirs executors administrators or assigns personally or by their agents workmen or servants at all time or times whenever it may suit their or any of their convenience to enter into and upon and pass over any part or parts of the above described premises and to explore search for and excavate any and every kind of ore mineral metal or coal and to dig excavate or penetrate any part of the said premises and at all times to have free ingress and egress for themselves or their heirs executors administrators or assigns or their workmen or persons employed by them or either of them with or without horses teams oxen mules carts sleds or wagons to dig mine raise and take remove and carry away any and every kind of ore mineral metal or coal which may be found or discovered in or upon any part or parts of the hereby granted bargained and sold land provided always that such digging explorations or searches shall *425be conducted with as little injury or damage to the said Jacob g. Young Jacob P. Findlay and William E. Young [the grantees] their heirs or assigns as shall be practicable consistently with the success of the same and the said Jacob g. Young, Jacob P. Findlay and William R. Young do hereby for themselves their heirs executors administrators and assigns covenant grant promise and agree to and with the said parties of the first part hereto their heirs executors administrators and assigns that neither of them shall and will at any time or times or in any manner hinder impede delay or in anywise obstruct the full and free exercise of all any and every the rights and privileges herein reserved or conditioned and that neither of them shall or will at any time or times or in any manner interfere with the property and ownership hereby reserved to the said parties of the first part hereto of all and every the mines metals minerals coal ore or ore-banks in or upon the above described tracts or parcels of land by these presents bargained and sold to the said Jacob g. Young Jacob P. Findlay and William R. Young their heirs and assigns.”
The title of William Rawle et ah, grantors, to the reservation of the mineral rights descended through mesne conveyances to Donald E. Fisher, the present defendant; the title of Jacob S. Young et al., grantees, to the surface of the land descended through mesne conveyances to the Commonwealth of Pennsylvania, the present plaintiff. The tract in question was purchased by the Commonwealth with moneys of the Game Commission License Fund. It is mountain land which has been timbered over; it is held by the Commonwealth as a game habitat; it contains no buildings, railroad lines, public highways, or improvements of any kind. It is largely underlain with bituminous coal which, for the past fifteen years, defendant has been deep mining, but which he has now started to strip mine in order to excavate coal which can be removed in no other manner. *426The area of coal thus far uncovered is approximately 2800 feet long and from 38 to 70 feet wide; the vein is about 42 inches thick; the overburden removed averages in depth from 12 to 20 feet. In compliance with the Bituminous Coal Open Pit Mining Conservation Act of 1945 defendant has filed a bond and has contracted for the back filling of the stripping operation.
Plaintiff filed the present bill in equity to restrain defendant from further strip mining on the tract. It contends that defendant has no right to practice that method of digging because the use of power machinery to remove the overburden was not a customary method of mining bituminous coal in 1855 when the mineral rights were separated from the title to the surface, and also because plaintiff is entitled by law to surface support. Defendant filed an answer to the bill, but there is no dispute as to the facts. The court below granted the injunction prayed for, and defendant appeals.
Neither of the grounds on which plaintiff relies can be sustained. Defendant, as assignee of the grantors under the deed of 1855, acquired the “full, entire, complete and exclusive ownership” of the coal “in or upon any part of” the land with the right to “dig, excavate or penetrate any part of the said premises”. There is no restriction limiting that right nor any provision as to the method of severing the coal. What was said in Richardson v. Clements, 89 Pa. 503, 506, is applicable here, viz.: “The language used indicates no intention to deny the use of such improved process as science may discover or mechanical ingenuity invent. . . .” Plaintiff admits that the coal which defendant seeks to obtain by stripping operations cannot be recovered by any other process. True it is that strip mining was not used in 1855 in the case of bituminous deposits although it was the earliest known method in Pennsylvania of mining anthracite coal and was originally performed by hand; the invention and use of power shovels for the re*427moyal of the overburden was, of course, a later development, but there is no rule of law which would preclude defendant, having the right to mine the coal, from using methods for that purpose made possible by modern machinery and inventions. It was said in Oberly v. H. C. Frick Coke Co., 262 Pa. 83, 87, 104 A. 864, 865: “The right to work the mine involves the right to penetrate the surface of the soil for the minerals, to remove them in the manner most advantageous to the mine owner, and to use such means and processes in mining and removing them as may be necessary in the light of modern improvements in the arts and sciences.” We said in Taylor v. Heffner 359 Pa. 157, 163, 58 A. 2d 450, 453: “It cannot be said that because motor vehicles were rarely used at the creation of the right of way that it was within the contemplation of the parties not to permit the dominant estate to use improved means of travel. Where, as here, the grant of the easement is unrestricted, the grantee is given such rights as are necessary for the reasonable and proper enjoyment of the thing granted.” In Dowgiel v. Reid, 359 Pa. 448, 59 A. 2d 115, an easement of a “private road or cartway” was created in 1835; the present owners of the easement proposed to erect poles and to string copper wire along the road for the purpose of providing their farm with electrical facilities. We held that they had the right so to do even though, when the easement was granted, the only need for the road was as a pathway over which pedestrians, horses and vehicles could travel, and telephones, electric lights and other electrical devices were, of course, totally unknown. The opinion (p. 453, A. p. 118) contained a quotation from 19 C. J. 975, 976 [§219] b. to the effect that “Where a way is granted or reserved without any limitation as to its use, it will not necessarily be confined to the purposes for which the land was used at the time the way was created, but may be used for any purpose to which the land aceommo*428dated by tbe way may naturally and reasonably be deself of modern inventions if by so doing he can more fully exercise and enjoy or carry out the object for which the way was granted.” The application of the principle illustrated by these authorities clearly establishes defendant’s right to excavate the coal of which he is the owner by a method presently in use for that purpose even though not anticipated, perhaps, by the parties to the deed of 1855.
As to defendant’s alleged legal duty to support the surface of the land it must be conceded that, if such a duty exists, he cannot dig away and destroy the surface down to the subjacent vein of coal, for the physical injury to plaintiff in that event would obviously be the same as if the surface were allowed to subside due to lack of support from beneath. No principle of law is more firmly established in this Commonwealth than that, where there is a severance of the mineral rights from the title to the surface, the owner of such rights is obligated to support the superincumbent estate; the owner of the surface is entitled to that support, not as an easement or right depending on a supposed grant, but as a proprietary right at common law.1 The owner of the *429surface may, however, by contract or by waiver, relinquish the right,2 although such relinquishment should not be implied in the absence of language clearly indicating the intention of the parties to that effect.3 In this case the deed of 1855 did, in our opinion, impliedly release to the grantors the obligation of surface support. It reserved to them the “ownership and right” of the coal “as though the present conveyance had not been made”, and irrespective of whether the coal was “in or upon any part of” the land. It further reserved to them “the full, free, absolute and exclusive right and authority ... to excavate” the coal and “to dig, excavate or penetrate any part of the said premises” for that purpose. It provided that “such digging . . . shall be conducted with as little injury or damage” to the grantees “as shall be practicable consistently with the success of the same in other words, the success of the digging and removal of the coal was to be the paramount objective, and the *430grantors were to have the right to conduct their enterprise successfully and to the fullest extent no matter what the injury or damage to the surface provided it be as little as practicable. The grantees of the surface agreed that they would not “in any manner hinder, impede, delay, or in anywise obstruct the full and free exercise of all, any and every, the rights and privileges . . . reserved” by the grantors. Whether a deed impliedly releases the right of surface support must depend in each instance upon its terms; here the cumulative effect of its provisions would seem fairly to give to the grantors, and their assigns, who reserved the ownership and authority to excavate the coal, the right to remove all of it whether upon the land, or near the surface, or lying deep within it, and by any method, old or new, appropriate and necessary for the purpose.
It may be added that it is doubtful whether, in any event, plaintiff would be entitled here to equitable relief. The tract in question is unimproved mountain land; any damage caused to its surface would be merely of a temporary nature in view of the provisions of the Bituminous Coal Open Pit Mining Conservation Act of May 31, 1945, P. L. 1198, as amended by the Act of May 23,1949, P. L. 1730, which provides that before any operator shall engage in open pit mining of bituminous coal he must file a bond conditioned for the faithful performance of all the requirements of the Act, one of which is that he must, within one year after the operation is completed, place sufficient overburden or earth in the open cut to cover the exposed face of the unmined coal, and, within three years after the operation is completed or abandoned, plant trees, shrubs or grasses upon the land affected thereby. Even before the enactment of this statute it was held in a number of cases, under circumstances somewhat similar to those here present, that relief by injunction would be denied and the owner of the surface left to his remedy to recover damages in *431an action at law: Berkey v. Berwind-White Coal Mining Co., 220 Pa. 65, 69 A. 329; 229 Pa. 417, 78 A. 1004; Woods v. Pittsburg Coal Co., 230 Pa. 197, 79 A. 499; Plummer v. Hillside Coal & Iron Co., 96 Pa. Superior Ct. 180.
The decree is reversed at plaintiff’s costs. The record is remanded to the court below with direction to retain the bill ior any application that may be made by plaintiff hereafter to compel defendant’s compliance with his obligation to replace the overburden and make the plantings as provided by statute.
Jones v. Wagner, 66 Pa. 429; Coleman v. Chadwick, 80 Pa. 81; Carlin & Co. v. Chappel, 101 Pa. 348; Pringle v. Vesta Coal Co., 172 Pa. 438, 33 A. 690; Robertson v. Youghiogheny River Coal Co., 172 Pa. 566, 33 A. 706: Noonan v. Pardee, 200 Pa. 474, 50 A. 255; Youghiogheny River Coal Co. v. Allegheny National Bank, 211 Pa. 319, 60 A. 924; Berkey v. Berwind-White Coal Mining Co., 229 Pa. 417, 78 A. 1004; Penman v. Jones, 256 Pa. 416, 100 A. 1043; Lenox Coal Company v. Duncan-Spangler Coal Co., 265 Pa. 572, 109 A. 282; Charnetski, Administrator, v. Miners Mills Coal Mining Co., 270 Pa. 459, 113 A. 683: Smith v. Glen Alden Coal Co., 347 Pa. 290, 304, 32 A. 2d 227, 235; Pennsylvania Coal & Coke Corporation v. Duncan-Spangler Coal Co.. 132 Pa. Superior Ct. 533, 1 A. 2d 511; (aff. 333 Pa. 272, 3 A. 2d 356).
Scranton v. Phillips, 94 Pa. 15, 21, 22; Madden v. Lehigh Valley Coal Co., 212 Pa. 63, 61 A. 559; Miles v. Pennsylvania Coal Co., 214 Pa. 544, 63 A. 1032; 217 Pa. 449, 66 A. 764; Kellert v. Rochester & Pittsburg Coal & Iron Co., 226 Pa. 27, 74 A. 789; Stilley v. Pittsburgh-Buffalo Company, 234 Pa. 492, 83 A. 478; Graff Furnace Co. v. Scranton Coal Co., 244 Pa. 592, 91 A. 508; Kirwin v. Delaware, Lackawanna & Western R. R. Co., 249 Pa. 98, 94 A. 468; Miles v. The New York, Susquehanna & Western Coal Co., 250 Pa. 147, 95 A. 397; Gordon v. Delaware, Lackawanna & Western R. R. Co., 253 Pa. 110, 97 A. 1032; Commonwealth v. Clearview Coal Co., 256 Pa. 328, 100 A. 820; Weakland v. Cymbria Coal Co., 262 Pa. 403, 105 A. 558; Atherton v. Clearview Coal Co.. 267 Pa. 425, 110 A. 298; Householder v. Quemahoning Coal Co., 272 Pa. 78, 116 A. 40.
Coleman v. Chadwick, 80 Pa. 81; Williams v. Hay, 120 Pa. 485, 14 A. 379; Robertson v. Youghiogheny River Coal Co., 172 Pa. 566, 33 A. 706: Weaver v. Berwind-White Coal Co., 216 Pa. 195, 65 A. 545; Dignan v. Altoona Coal & Coke Co., 222 Pa. 390, 71 A. 845; Penman v. Jones, 256 Pa. 416, 100 A. 1043; Hines, Director General, v. Union Connellsville Coke Co., 271 Pa. 219, 114 A. 521; Pennsylvania Coal & Coke Corporation v. Duncan-Spangler Coal Co., 132 Pa. Superior Ct. 533, 1 A. 2d 511; (aff. 333 Pa. 272, 3 A. 2d 356).