it had knowledge, at the time, that the value of the property was materially less than their estimate. And from the nature of the property, and its imperfectly developed condition, such knowledge was impossible. No one could know its actual value until further development was made. Until then, any estimate must have been entirely speculative and conjectural. It would depend as much, perhaps, upon the temperament and expectations of the party making it as upon any knowledge of facts. The law does not hold one responsible for the extravagant notions he may entertain of the value of property, dependent upon its future successful exploitation, or the result of future enterprises; nor for expressing them to one acquainted with its general character and condition. How could an over-estimate in such a case be shown? Other estimates would be equally conjectural. The law does not fasten responsibility upon one for expressions of opinion as to matters in their nature contingent and uncertain. Such opinions would probably be as variant as the individuals who give them utterance. A statement of an opinion assigning a certain value to property like a mine or a quarry not yet opened is not to be pronounced fraudulent because the property upon subsequent development may prove to be worthless; nor is it to be pronounced honest because the property may turn out of much higher value. Whenever property of any kind depends for its value upon contingencies which may never occur, or developments which may never be made, opinion as to its value must necessarily be more or less of a speculative character; and no action will lie for its expression, however fallacious it may prove, or whatever the injury a reliance upon it may produce. The determination of its truth or falsity, until the contingency occurs or becomes impossible, would lead the courts into investigations for which they have no fixed rules to guide their own judgments or to instruct juries. For opinions upon matters capable of accurate estimation by application of mathematical rules or scientific principles, such, for example, as the capacity of boil ers, or the strength of materials, the case may be different. So, also, for opinions of parties possessing special learning or knowledge upon the subjects in respect to which their opinions are given, as of a mechanic upon the working of a machine he has seen in use, or of a lawyer upon the title of property which he has examined. Opinions upon such matters are capable of approximating to the truth, and for a false statement of them, where deception is designed, and injury has followed from reliance on them, an action may lie.¹ 1 Gordon v. Butler, 105 U. S. 553, 556-58 (1881), Field, J., citing Holbrook v. Connor, 60 Me. 578 (1872), - in which, to induce a sale, representations were made that untested land contained oil, a fact unknown except as inferred from the production of wells on neighboring lands, and from a well upon the land itself; and in which it was held, also, that an action would not lie for a false statement as to the price the vendor had paid for the land, ib. 582, cases, - two judges, out of the seven, dissenting, ib. 585-91, cases. In Southern Development Co. v. Silva, 125 U. S. 247, 252 (1888), the principle stated in the text was applied in a suit to reValued. With value agreed upon: as, a valued policy of insurance, q. v. See APPRAISE; DESCRIPTION, 4; IMPAIR; JUST, 2: In the Revised Statutes, acts and resolutions of Congress, includes every description of carriage or other artificial contrivance used, or capable of being used, as a means of transportation on land. A ferry-boat is not a vehicle, within a statute providing for a specific tax on "carriages and other vehicles used for passengers for hire." s But a street-sprinkler is a "public vehicle," within an ordinance imposing a license upon public vehicles using streets for trade or traffic. The phrase "or other wheeled vehicle of whatever description," used in a statute, following such specified vehicles as "carriages, wagons, buggies, sleighs and sleds," was held to refer to vehicles of the same scind a contract for the purchase of a silver mine on the ground of fraud in representations as to the probable amount of mineral it would yield, and to recover the consideration paid. 1 Chidester v. State, 25 Ohio St. 438 (1874), Rex, J. 2 L. varius, diverse, changing. Whence variant. • See Nash v. Towne, 5 Wall. 698 (1866). 4 House v. Metcalf, 27 Conn. 638 (1858), Sanford, J.; 30 id. 57; 72 111. 229. • Roberts v. Graham, 6 Wall. 581 (1867), cases; 18 Bradw. 43, 491. See Gould, Pl., pp. 28, 62, 421. L. vehere, to carry, convey. R. S. § 4: Act 18 July, 1866, § 1. • Duckwall v. New Albany, 25 Ind. 286 (1865). • St. Louis v. Woodruff, 71 Mo. 92 (1879).