In case lands sought to be appropriated by any railroad company in this state for depot purposes belong to private persons, and such company and the owner cannot agree on the compensation to be paid, or in case the owner is incapable of contracting, be unknown or a nonresident of the state, such company may have such lands condemned in the manner that is provided in chapter 523 for assessing damages which the owners of lands may severally sustain in consequence of the erection, establishment and maintenance of railroads over such lands; provided, that in no case shall more than ten acres of land in the country or more than six blocks in a town, village or city, be condemned under chapter 523 at any one place, or for any one depot; and provided further, that any other railroad company shall have the right to use said depot grounds for depot purposes with the necessary buildings, turnouts, sidings, switches and other conveniences in furtherance of said purpose; and if the said two companies cannot agree upon the amount of compensation to be made therefor, or the points or manner of such use, the same shall be ascertained and determined by commissioners, as provided by law for the condemnation of land for railroad purposes.