The right of the State to tax all real property situated within its 'borders,29 has never been questioned. Its inability to tax real Constitutional Limitations Upon Taxing Powers. 947 property beyond its borders is equally uncontested. In these respects tangible personal property is grouped with real property. The legal principle mobilia sequuntur personam operates to permit the taxation of intangible personal property by a State in which its owner is domiciled even though the instruments evidencing its existence and ownership be in another State; and, conversely, it permits the State where these instruments are situated to tax them although their owner be domiciled in another State.

28 188 U. S. 385; 23 Sup. Ct. Rep. 463; 47 L. ed. 513.

29 Excepting, of course, property owned by the United States or by foreign governments.

That tangible personal property may be taxed by the State within which it is situated has not been seriously questioned.30

That tangible personal property situated in one State may not be taxed by another State, even though its owner be domiciled therein, is definitely stated in Union Refrigerator Transit Co. v. Kentucky.31 decided in 1905. In this case was presented the question whether a corporation organized under the laws of Kentucky might be assessed upon its rolling stock permanently located in other States and employed there in the prosecution of its business. The court, in its opinion, say: "The argument against the taxability of land within the jurisdiction of another State applies with equal cogency to tangible personal property beyond the jurisdiction. It is not only beyond the sovereignty of the taxing State, but does not and cannot receive protection under its laws. True, a resident owner may receive an income from such property, but the same may be said of real estate within a foreign jurisdiction. Whatever be the rights of the State with respect to the taxation of such income, it is clearly beyond its power to tax the land from which the income is derived."

Continuing the court point out that the doctrine as to intangible personalty has no application.

30 See, for example, Coe v. Errol, 116 U. S. 517; 6 Sup. Ct Rep. 475; 29 L. ed. 715; Brown v. Houston, 114 U. S. 622, 5 Sup. Ct. Rep. 1001, 29 L. ed. 257, and other eases discussed in § 332 relating to the taxation by the State of articles of interstate commerce.

31 199 U. S. 194; 26 Sup. Ct. Rep. 36; 50 L. ed. 150.

"The arguments in favor of the taxation of intangible property at the domicile of the owner," the court say, "have no application to tangible property. The fact that such property is visible, easily found, and difficult to conceal, and the tax readily collectible, is so cogent an argument for its taxation at its situs, that of late there is a general concensus of opinion that it is taxable in the State where it is permanently located and employed, and where it receives its entire protection, irrespective of the domicile of the owner. We have, ourselves, held in a number of cases that such property, permanently located in a State other than that of its owner, is taxable there." 32

32 After citing earlier cases decided by itself, the Supreme Court continue: "There are doubtless cases in the state reports announcing the principle that the ancient maxim mobilia sequuntur personam still applies to personal property, and that it may be taxed at the domicile of the owner; but upon examination they all, or nearly all, relate to intangible property, such as stocks, bonds, notes, and other choses in action. We are cited to none applying this principle to tangible personal property, and after a careful examination have not been able to find any wherein the question is fairly presented, unless it be that of Wheaton v. Mickel (67 N. J. L. 525, 42 Atl. 843) where a resident of New Jersey was taxed for certain coastwise and seagoing vessels located in Pennsylvania. It did not appear, however, that they were permanently located there. The case turned upon the construction of a state statute and the question of constitutionality was not raised. If there are any other cases holding that the maxim applies to tangible personal property, they are wholly exceptional, and were decided at a time when personal property was comparatively of small amount, and consisted principally of stocks in trade, horses, cattle, vehicles, and vessels engaged in navigation. But in view of the enormous increase of such property since the introduction of railways and the growth of manufactures, the tendency has been in recent years to treat it as having a situs of its own for the purpose of taxation, and correlatively to exempt it at the domicile of its owner." Finally, the court say that the question is, in fact, completely covered in the two recent cases of Louisville & Jeffersonvilie Ferry Co. v. Kentucky, 188 U. S. 385; 23 Sup. Ct. Rep. 463; 47 L. ed. 513, and Delaware, L. & W. R. Co. v. Pennsylvania, 198 U. S. 341; 25 Sup. Ct. Rep. 669; 49 L. ed. 1077.

The first of these two cases we have already considered. In the second it was held that including in the appraisement of the capital stock of a domestic corporation, for purposes of taxation, the value of coal mined by it within the State, but situated within other States there awaiting the sale was in excess of the State's taxing power. The supreme court of the State having held that the tax on the value of the capital stock was a tax on the property and assets of the corporation issuing the stock, and it having been repeatedly in the State bears to the entire business done by the company, or the mileage of tracks of a railway company, or of wires, of a telegraph or telephone company, bears to the entire mileage of tracks or wires of the company taxed.