or potential existence at the time when the loan was made and the mortgage given. It is the usual course of procedure in the construction of a railroad that money is raised by mortgage upon its property, and that the structure is built and operated to a large extent by means of the loans thus obtained, and much of the property is created and acquired after the loan is made. The statute makes no distinction between property necessary for the completion and furnishing of the road and that which is essential to its operation. By the terms of the law, therefore, it was contemplated that for the money thus obtained the property acquired should be pledged as the security for its repayment, and this cannot be accomplished without holding that the lien of the mortgage attaches to such property as shall be necessary for that purpose, whether in existence at the time when the mortgage is given or is subsequently acquired, and whether such property be such as is denominated “real” or “personal.” So it was early held that such a mortgage ■created, in equity, a lien upon property subsequently acquired superior to the lien of a subsequent incumbrancer by mortgage or judgment. Seymour v. Railroad Co.,
25 Barb. 284 ; Benjamin v. Railroad Co., 49 Barb. 447 ; Stevens v. Watson, 4 Abb. Dec. 302. In those cases the question arose respecting liens upon subsequently acquired real property. But the discussion shows that the court considered the rule applicable as well to personal as to real property. Such has been the uniform rule applied in the federal courts. Mitchell v. Winslow, 2 Story, 630 , Fed. Cas. No. 9,673; Trust Co. v. Kneeland, 138 U. S. 419 , 11 Sup. Ct. 357 . The difficulties which have arisen relate not so much to the recognition of the mortgage as a lien, for the doctrine of the above-cited cases has never been questioned, but rather to the steps necessary to be taken to evidence the lien. The first debate arose over the question whether the rolling stock and equipment of the road retained its character as personal property, and, if so, was it requisite that it should be filed as a mortgage of chattels. The supreme court divided upon the question, and decisions were rendered both ways. The court of appeals in Hoyle v. Railroad Co.,
54 N. Y. 314 , settled the question by holding that it was personal property, and that the mortgage covering it must be filed as a mortgage of chattels, as prescribed by the act of 1833, or the same would be void as against the general creditors of the corporation. To meet this conclusion, the legislature in 1868 passed an act (Laws 1868, c. 779), providing that it shall not be necessary to file such mortgage as a mortgage of chattels when it covers real and personal property, and is recorded as a mortgage of real estate in each .county in or through which the railroad runs. By this act the status of such property, so far as it relates to liens by way of mortgage, is made practically subject to the same rules, .and is placed upon the same footing, as real property. The business carried on by railroads, the great extent of territory which they cover, and the fact that the rolling stock is at all times widely distributed, not only throughout the state through which its lines mainly run, but also throughout the different states of the Union, creates an essential difference between it and property whose situs