A contract of exemption from taxation must be clear and unambiguous ; City of St. Louis v. Ry. Co., 210 U. S. 266, 28 Sup. Ct. 630, 52 L. Ed. 1054 ; exemption is never pre sumed ; New York v. Tax Com'rs, 199 U. S. 41, 25 Sup. Ct. 705, 50 L. Ed. 65, 4 Ann. Cas. 381; exemption acts, if doubtful, are con strued in favor of the public ; Spokane Val ley L. & W. Co. v. Kootenai Co:, 199 Fed. 481; Commonwealth's Appeal, 127 Pa. 435, 17 Atl. 1094 ; being iu derogation of common right ; Yazoo & M. V. R. Co. v. Thomas, 132 U. S. 174, 10 Sup. Ct. 68, 33 L. Ed. 302. The rule that they must be strictly construed against the exemption applies not only to the extent of the legislative grant, but also to the power of the legislature to make it. Ber ryman v. Board of Trustees, 222 U. S. 334, 32 Sup. Ct. 147, 56 L. Ed. 225. Exemptions are not favored by the courts ; People v. Com missioners, 76 N. Y. 64; property exempted from taxation must be of a public nature and for a public purpose. Where the general use is of a public nature the right to exemption is not impaired by the fact that part of the property is used for producing revenue, as in the case of a public library, and statu tory exemption is not impaired by the fact that part of a library building is a theatre or hall occasionally let to outside parties; People v. Sayles, 23 Misc. 1, 50 N. Y. Supp. 8.
The legislature of a state may grant to a corporation a perpetual exemption from tax ation; Herrick v. Randolph, 13 Vt. 525; Lan don v. Litchfield, 11 Conn. 251; O'Donnell v. Bailey, 24 Miss. 386 ; but privileges which may exempt a corporation from the burdens common to individuals do not necessarily flow from their charter, but must be express ed in it or they do not exist ; Marshall, C. J., in Providence Bank v. Billings, 4 Pet. (U. S.) 514, 7 L. Ed. 939.
A state may bind itself by a contract, based upon a consideration, to refrain from exercising the right of taxation in a partic ular case ; Tomlinson v. Branch, 15 Wall. (U. S.) 460, 21 L. Ed. 189 ; Humphrey v. Pe gues, 16 Wall. (U. S.) 244, 21 L. Ed. 326; At water v. Woodbridge, 6 Conn. 223, 16 Am. Dec. 46, note. Immunity from taxation is not in itself transferable. It must be consid ered as a personal privilege not extending beyond the immediate grantee, unless other wise expressly declared; Pickard v. R. Co., 130 U. S. 637, 9 Sup. Ct. 640, 32 L. Ed. 1051.
A charter of a. railway conferring all the powers and privileges conferred by act on another company does not include a right to exemption belonging to such other company; Wright v. Banking Co., 216 U. S. 420, 30 Sup. Ct. 242, 54 L. Ed. 544. A right of exemption belonging to a railroad company does not survive a foreclosure sale at which the state bought in the property ; Great Northern R.
Co. v. Minnesota, 216 U. S. 206, 30 Sup. Ct. 344, 54 L. Ed.. 446.
A distinction between an exemption con tained in a special charter, and general en couragement to all persons to engage in a certain class of enterprises, is well settled ; the latter is a mere announcement of a pol icy of the state, and not a contract with a company coming under its provisions ; Wis consin & M. R. Co. v. Powers, 191 U. S. 379, 24 Sup. Ct. 107, 48 L. Ed. 229.
Where the exemption is by contract with the state (as in the Dartmouth College Case, 4 Wheat. [U. S.] 518, 4 L. Ed. it is beyond the power of the state to abrogate. To make such a contract there must be a consideration. if the law be a mere offer of a bounty, it may be withdrawn at any time, notwithstanding the recipients may have incurred expense upon the faith of, such offers; 'Grand Lodge F. & A. M. v. New Orleans, 166 U. S. 143, 17 Sup. Ct. 523, 41 L. Ed. 951. Thus in Welch v. Cook, 97 U. S. 541, an act exempted from general taxa-1 tion for ten years property that might be employed in the District of Columbia for manufacturing purposes; it was held to be merely a bounty and liable at any time to be withdrawn. So the perpetual exemption in Christ Church v. Philadelphia Co., 24 How. (U. S.) 300, 16 L. Ed. 602, was held revocable at the pleasure of the sovereign. The same test as to what constitutes public purposes should be applied in exempting property from taxation as in levying taxes ; 18 Harv. L. Rev. 386.
The exemption of corporate capital does not necessarily include the exemption of shareholders on their stock; New Orleans v. Bank, 167 U. S. 404, 17 Sup. Ct. 905, 42 L. Ed. 202. ' A grant of a franchise subject to paying a license fee does not,, of itself, exempt the property itself from taxation; New York v. Tax Com'rs, 199 U. S. 48, 25 Sup. Ct. 705, 50 L. Ed. 65, 4 Ann. Cas. 381; and the imposition of an occupation tax does not exclude the right to tax a vehicle used therein ; Newport v. Fitzer, 131 Ky. 544, 115 S. W. 742, 21 L. R. A. (N. S.) 279. An ex emption, when contrary to the constitution of a state, cannot be obtained in the guise of a contract ; Forshaw v. Laynan, 182 Fed. 193, 104 C. C. A. 559.
The state may exempt property from tax ation for state purposes that is subject to taxation for municipal purposes; Coving ton Gas Light Co. v. Covington, 92 Ky. 312, 17 S. W. 808. It has full power to ex empt any class of property as it may deem best, according to its views of public policy; Wilkens Co. v. Baltimore, 103 Md. 293, 63 Atl. 562, 7 Ann. Cas. 1192 ; as stock and se curities of building associations; National L. & I. Co. v. Detroit, 136 Mich. 451, 99 N. W. 380.