some contingency that must happen,1 and the intermediate time must be filled by some subsisting estate, as a tenancy to commence on the happening of a contingency, and leaving a possible interval unfilled, is not, in law, considered a good estate. The time when the lessee commences to pay his royalty, is, in some cases, the commencement of his tenancy, but the tenancy under a verbal lease commences when the tenant takes possession of the premises.4 Certainty of continuance is also an essential to a term for years and the estate may be limited either absolutely or contingently upon the happening of some certain event.5 And when the duration of the tenancy is fixed and certain it will terminate without demand and notice by the lessor, and in the case of a tenancy for years, upon the last moment of the anniversary of the day from which the tenant was to hold, in the last year of his tenancy.7

May be perpetual.

§ 134. Same There is no limitation to the extent of a tenancy for years, and mining leases, like other leases for real estate, may be of perpetual duration, and this is the law, both in England and the United States. The manor leases in New York and the fee farm leases in Pennsylvania, are the most common illustrations of this kind of lease,8 but they will apply as well to mining as to other species of property, and will be equally valid, whether they are in the form of a grant of land in

1 Finkelmeier v. Bates, 10 N. Y. S. C. 483; Taylor's Land. & Ten., $ 95.

2 Taylor's Land. & Ten., § 72, p. 83.

3 The payment of royalty is prima facie evidence of the existence of

the tenancy. Taylor's Land. & Ten., § 69.

4 Evans v. Winona Land. Co., 30 Minn. 515.

5 Taylor's Land. & Ten., § 75, p. 85, and cases cited.

6 Fox v. Nathans, 32 Conn. 348.

See as to rule of computation of terminal days, Taylor's Land. &

Ten., § 78, p. 89.

8 Taylor's Land. & Ten., § 74, 261-440.

fee, reserving an annual rental,1 or a conveyance of an ordinary tenancy, based upon a present consideration.2 The provision is quite frequent in leases of mining property, as a limitation of the tenancy, that the lease shall continue so long as the lessee shall continue to pay the royalty and perform his part of the covenants contained in the lease,3 but where the lessee covenants also to pay the royalty, and perform the covenants on his part, this is construed to be a perpetual lease.4 It could be forfeited by the lessor for a failure to perform the covenants, but as long as he complies with the conditions of the lease, the tenancy could only be terminated by the consent of both parties to the lease.5 A lease to continue as long as the property demised is used for certain purposes, although for a present money consideration, is held to be a lease in perpetuity at the will of the lessee and to convey a base or terminable fee.6 The fee in lands may also be granted by instruments in which rent or royalty is reserved to be paid, and covenants may be inserted to enforce the performance by the grantee.7 But such instruments are conveyances, rather than leases, and the only similarity between the two is the reservation of the rent or royalty,

1 Ante, idem; Saunders v. Hays, 44 N. Y. 79. For an oil lease, without limitation as to time, which provided for a fixed annual payment in lieu of work or forfeiture, which was held to create a perpetual lease, so long as oil or gas was produced, see Lowther Oil Co. v. Duffy (W. Va. 1903), 43 S. E. Rep. 101.

2 Watterson v. Reynolds, 95 Pa. St. 474.

3 Wallace v. Hormstead, 44 Pa. St. 492; Phil. &c. Co. v. Beaumont, 39 Pa. St. 43.

4 Ante, idem.

5 Folts v. Huntley, 7 Wend, 210; cited Tay. Land. & Ten., § 74.

6 Taylor's Land. & Ten., supra; Delhi School Dist. v. Everett, 52

Mich. 314. But see Lemington v. Stevens, 48 Mich. 38.

7 Van Rensseller v. Reed, 26 N. Y. 558; cited Taylor's Land. & Ten., p. 433.

and the covenants to secure the payment thereof by the grantee.1

§ 135. Right to remove fixtures and machinery. As a general rule a lessee has the right, at the termination of the lease, to remove such machinery as he may have placed on the demised premises during the continuance of the tenancy.2 The same rule applies as in the case of a license and in the absence of a covenant not to remove the machinery at the termination of the lessee's rights, he may enter upon the premises and have the right of ingress and egress and a reasonable time to remove the same, and the fact that the mine would be injured by the removal of the machinery would not affect his right. But where the lessee covenanted not to remove the machinery he will not be permitted to do so, and an injunction would

1 Taylor's Land & Ten., supra.

2 Rolleston v. New, 4 Kay & J. 640; MacSwinney on Mines, p. 246; s. c. Mor. Min. Dig., p. 201.

3 Desloge et al. v. Pierce, 38 Mo. 588.

Foley v. Brown v.

Rolleston v. New, supra, where the principal reason for the refusal of the injunction to prohibit the removal of the machinery was based upon the fact that the lessor had not given lessee notice of his intention to purchase, or paid the value of the machinery. The following cases recognize the lessee's right to remove fixtures, at end of term: Addenbroke, 13 M. & W. 174; Lawton v. Lawton, 3 Atk. 13; Elect. Lt. Co., 55 Fed. Rep. 229; Nelson v. Howson, 122 Ala. 573; Cooper v. Johnston, 143 Mass. 108; Lake Sup. Can. Co. ». McCann, 86 Mich. 106; Thomas v. Davis, 76 Mo. 73; Richardson v. Koch, 81 Mo. 264; Cassell v. Crothers, 193 Pa. St. 359; 20 Am. & Eng. Enc. Law. (2 Ed.), 785. The casing and derrick used in an oil well can be removed by lessee during term, or within a reasonable time afterwards. Sheller v. Shivers, 171 Pa. St. 569; 33 Atl. Rep. 95. Although the lease provides that improvements are to remain on expiration of lease, it is held this refers only to improvements in the nature of repairs, and lessees are entitled to remove a hauling system put in by them. Beech Cr. Coal Co. v. Mitchell, 193 Pa. St. 112; 44 Atl.

Rep. 245.

lie to compel a performance of the covenant.1 A covenant to keep the machinery in repair and deliver it up at the termination of the tenancy, is a covenant that the courts will enforce, and as such a covenant runs with the land and is a continuous benefit to the mine, it would pass to the grantee of the reversion and could be enforced at the end of the term.2 A covenant to permit the lessor, at any time he so desired, to purchase the machinery at its value, or to take any part thereof, would not be enforced, however, on account of being injurious and oppressive, and the court would refuse to grant an injunction to prevent the breach of such a covenant.3

1 Hamilton v. Dunsford, 6 Ir. Ch. 412. And see also, where such a covenant was enforced, Storer v. Hunter, 3 B. & C. 368; 5 D. & R. 240. 2 MacSwinney on Mines, p. 246; Easterly v. Sampson, 1 Cr. & J. 105. And see Foley v. Addenbrook, 13 M. & W. 174, and Beaufort v. Bates, 3 DeG. F. & J. 381.

Talbot v. Ford, 13 Sim. 173; Rolleston v. New, supra, already explained in note. Machinery which can be removed by lessee without material injury to the freehold, does not become part of the realty. Hewitt v. Gen. Elect. Co., 164 Ill. 420. As to right of lessee of oil well to remove tubing, piping and tools, on expiration of lease, see Siler v. Globe Co., 21 Oh. Cir. Ct. Rep. 284.

CHAPTER X.

RIGHTS AND LIABILITIES OF LESSOR.

SECTION 136. Scope of present chapter.

137. In general.

138. In regard to lessor's reversionary interest.

139. Same-Lessor's implied right to surface support.

140. Penalty for improper working.

141. Lessor's liability to lessee.

142. Same-For injuries from defects in premises.

143. Risk assumed by lessee.

144. Liability to strangers.

145. Right of re-entry.

146. Continued

When same can be exercised.

§ 136. Scope of present chapter. It is impossible, in the short space devoted to this chapter, to treat of all the rights and liabilities of the respective parties, during the continuance of the tenancy, under the varying covenants which different mining leases may contain, and the author will, therefore, leave such rights and liabilities to be determined by the terms of the particular covenant, to which the parties have subscribed, as controlled by the rules and customs of different mining sections, and after premising that the lessor retains certain rights and assumes certain liabilities, even after parting with the possession, and that the lessee, on the other hand, assumes certain rights and obligations, by entering into possession, will proceed to examine the mutual rights and duties of these respective parties, in a general way, placing parties who execute leases for mining purposes in the same position as other lessors and lessees, but confining observations, as far as practicable, to persons in the former vocation only.

§ 137. In general. After the execution of a lease there are reciprocal rights and responsibilities attaching to