requires that all mines of iron ore on the premises shall be opened, used and worked,' in the usual and customary manner. The grant of the right to mine and the omission of words requiring operation does not indicate the inclusion of a covenant to, or a condition requiring operation, but the opposite. The consideration for the demise as expressed therein was the payment of the rents and royalties therein provided to be paid by the lessee, and 'the prompt, continuous and full performance of the covenants and agreements therein contained.' To give this part of the lease the meaning claimed for it, it would be as unnecessary as unwarranted to insert the word 'explorations' after 'prompt,' and word 'mining' after 'continuous.' The words are plain and their meaning not obscure. By payment of the rents and royalties as they fell due, and the prompt, continuous, and full performance of all other covenants-and we will add, conditions of the lease, whatever it is concluded they were, discharges the lessee respecting the consideration.

"The clause of the lease to which attention is specially directed comprises the eighth paragraph thereof, and reads:

"All mines of iron ore on said premises shall be opened, used and worked in such manner as is usual and customary in successful mining operations of similar character when conducted by the proprietors themselves, and so as not to do or permit any unnecessary or unusual injury to the same, or inconvenience or hindrance in the subsequent operations of any mine or mines on said premises. Said second party expressly covenants not to remove or impair any support, timber, frame works, shafts, ditches, tramways, or approaches necessary or convenient for the use or maintenance of such mines or other property or improvements, except as hereinafter provided, and all rock, earth, and rubbish taken from said mines shall be dumped in such places as not to interfere with the convenient working of any mine or mines on said premises.'

"It may be asserted that the above quoted clause, perhaps varying slightly in phraseology, will be found in almost every mining lease of a Michigan property, and it is a matter of common knowledge that it is intended, as the words of the clause plainly indicate, not to require the lessee to open, use, and work the

mine, but to fix and settle the manner in which the lessee, whenever he undertakes to do so, shall open, use, and work the mine. The object of the clause is to prevent a waste of ore and unapproved methods of mining, and to compel the lessee to leave the mine, upon termination of his lease by surrender or limitation, in a good, safe, workmanlike condition, and so that the lessor may, if he desires, further proceed with the operation of his property without the expense of reopening the same. But if it is concluded that the above-quoted clause constitutes an agreement 'to open, use, and work the mine in such manner as is usual and customary in successful mining operations of similar character when conducted by the proprietors themselves,' no evidence is recalled tending to show what is the usual custom of the proprietors of mining property respecting the opening up, using, and working thereof. Evidence was introduced touching the practice of lessees, but there are many considerations which would move a lessee to operate which would not affect the fee owner. We may not imply, in the absence of proof on the subject, what the fee owner would do, and if we were at liberty to do so, it cannot be said the implication would be warranted that the owner of a tract of land upon which iron is not known to exist, although financially able, would risk an outlay running possibly into $100,000, or even more, in searching for what he knew he might not find, when by standing by he could have the question whether ore existed on his land settled by the mining operations of his neighbor, without the risk of a single dollar.

"The fourth paragraph of the lease, which is commonly known as the 'minimum mining clause' reads:

""The party of the second part, having explored the said premises, represents that there exists thereon iron ore in paying quantities, and agrees that if in any calendar year, for any reason, it shall mine and remove less than ten thousand (10,000) tons of iron ore, it shall nevertheless pay as stipulated ground rent royalty at the rate of ten (10) cents per ton on ten thousand (10,000) tons; said ground rent to be paid quarterly and on the dates when royalty is due, as hereinbefore provided. If the ground rent has been paid in any year, and no ore or less than the minimum amount has been removed from the prop

erty by the party of the second part, the royalty paid on ore not removed may be applied as payments of royalty on ore exceeding ten thousand (10,000) tons removed in any succeeding year, but no excess product of any year shall be applied to the deficiency of any succeeding year.'

"The language of this clause established beyond question that the lessor contemplated that in some years no ore would be mined, and, anticipating that the lessee might elect not to mine, and, in order that he should nevertheless have a settled, steady, annual net income from the property during the continuance of the lease, he exacted, and the lessee covenanted to pay, all taxes levied on the land, and in addition, $1,000 in each year when no ore was mined, and at least $1,000 in each year whether ore was mined or not. The right of the lessee to mine or not to mine. is clearly recognized by this clause, not only when the mine would not produce 10,000 tons, or when the market would not take 10,000 tons, or when circumstances beyond control prevented the mining of 10,000 tons, but when, for any reason, mining from the point of view of the lessee was undesirable, and so, if we have evidence in the lease tending to support an implied covenant to operate, we have also in the lease evidence of equal, if not greater, weight, of opposite tendency, and therefore the raising of an implied covenant to operate is prevented by the familiar rule that an implied covenant will not be lightly raised, and never is justified, except where the evidence in support is clear and convincing.

"In support of the position that a covenant may, and that under the facts and circumstances of this case should, be found by implication, a long list of cases from other jurisdictions have been cited. These cases have been examined. Many of these cases concern leases for the operation of oil and gas wells. The effect of the subject-matter of such leases upon the development of the intention of the parties is apparent.

"Light will be thrown upon the language used, and the intention of the parties will be better reflected,' said Judge Van Devanter in Brewster v. Zinc Co., 140 Fed. 801 [72 C. C. A. 213], 'if consideration is given to the peculiar and distinctive features of the mineral deposits which are the subjects of the lease.

Oil and gas are usually found in porous rock at considerable depths under the surface of the earth. Unlike coal, iron, and other minerals, they do not have a fixed situs under a particular portion of the surface, but are capable of flowing from place to place and of being drawn off by wells penetrating their natural reservoir at any point. They are part of the land, and belong to the owner so long as they are in it, or are subject to his control; but when they flow elsewhere, or are brought within the control of another by being drawn off through wells drilled in other land, the title of the former owner is gone. So, also, when one owner of the surface overlying the common reservoir exercises his right to extract them, the supply as to which other owners of the surface must exercise their rights, if at all, is proportionately diminished.'

"The subject-matter of an oil or gas lease is migratory while the subject-matter of an iron ore lease is not. The less gas or oil, as the case may be, drawn out, the less the property will produce, while the less iron ore taken out the more remains in the mine.

"Of the other cases cited it will be sufficient to say that in none of them was the lease, or the situation of the parties, or the illuminating circumstances and surroundings, similar to this case. To review all these cases would not be profitable, as, perhaps, the preceding review of this case was unnecessary, inasmuch as the question whether a covenant to mine may, by implication, be found in the lease under consideration is settled in the negative by the statutes and decisions of our own State.

"Section 8959, 3 Comp. Laws, provides:

"No covenant shall be implied in any conveyance of real estate, whether such conveyance contains special covenants or not.'

"Section 8994, 3 Comp. Laws, provides:

""The term "conveyance," as used in this chapter, shall be construed to embrace every instrument in writing, by which any estate or interest in real estate is created, aliened, mortgaged or assigned; or by which the title to any real estate may be affected in law or equity, except wills, leases for a term not exceeding three years, and executory contracts for the sale or purchase of lands.'

"Section 50, 1 Comp. Laws, provides:

""The word "land" or "lands" and the words "real estate" shall be construed to include lands, tenements, and real estate, and all rights thereto, and interest therein.'

"Lieberthal v. Montgomery, 121 Mich. 369 [80 N. W. 115], was an action brought to recover rent paid in advance for the use of a storeroom which was damaged by fire. There was no covenant in the lease, which was in writing, to repay the rent in case of fire, and it was held under section 8959, above quoted, that no such covenant could be implied. Minnis v. Newbro-Gallogly Co., 174 Mich. 635 [140 N. W. 980, 44 L. R. A. (N. S.) 1110], was a bill by a tenant to compel his landlord to repair rooms occupied by the tenant which had been rendered untenantable by fire, and to decree damages for the failure of the landlord to make such repairs. The lease, which was for a term of nine years, did not contain a covenant on the part of the landlord to repair the premises. It was there held:

"There being no express covenant in this lease, on the part of defendant, to repair the premises, and the statute (section 8959, 3 Comp. Laws) referred to precluding, in our opinion, any inquiry as to whether or not a proper construction of the instrument might imply one, it follows that no relief in damages for breach or for specific performance could be granted, under the allegations and averments in complainant's bill.'

"See, also, Thorkildsen v. Carpenter, 120 Mich. 419 [79 N. W. 636], where it is held:

""Courts cannot read covenants into deeds. This would be in direct contravention of the statute.'

"Ziegler v. Coal Co., 150 Mich. 82 [113 N. W. 775, 13 Am. & Eng. Ann. Cas. 90], where it is held: 'covenants cannot be implied in conveying real estate.'

"Negaunee Iron Co. v. Iron Cliffs Co., 134 Mich. 264 [96 N. W. 468], and Blake v. Lobb's Estate [110 Mich. 608, 68 N. W. 427], are cited to the opposite effect. In neither of these cases was the question whether a covenant may be found in a deed or lease by implication involved, considered, or decided. In the Negaunee Iron Co. Case the meaning to be given certain words found in a deed was under considera