not interfere with the natural flow of water from adjoining land. These rights are styled in the French law, servitudes created by law, and they are dealt with under the heading of servitudes. The French Code contains no separate section relating to limits of ownership, consequently it was necessary to describe these rights as servitudes created by law and to class them with those created by the consent of the parties.
The Japanese and French Codes similarly provide that when several movable things belonging to different persons are so united that they can not be separated without injury, the whole or composite thing belongs, to the owner of the principal movable. The French Code, however, lays down minute criteria for determining which is the principal and which the accessory thing. The thing for whose use, ornament or complement, another thing has been united to it is, according to the French law, to be regarded as the principal thing. If these criteria are wanting, then the more valuable is to be regarded as the principal; if the values are equal, then the larger in size is to be considered. The framers of the Japanese Code, deeming the question of principal and accessory to be one of fact, thought it would be unwise to enter too much into details. Accordingly Japanese law leaves the solution of the question entirely to the discretion of judges who, it is presumed, are best able to do substantial justice in each case, and when it is impossible to determine which is the principal and which the accessory, the composite thing is held in joint ownership.
Superficies and Emphyteusis. — A superficiary is one who has the right to use the land of another person for the purpose of owning thereon buildings, or bamboos and trees. This is the definition of the Japanese Civil Code. It is a right to use the land of another, and its object is limited to the ownership of buildings, or bamboos and trees. Bamboos and trees (chikuboku in Japanese) is a peculiar expression used to denote grasses, bushes, bamboos and trees, that is, all kinds of plants found in Japanese gardening. This species of right is created for residential purposes. For agricultural purposes, a similar right under the name of emphyteusis is established. There is no special provision in the French Code concerning superficies, and French jurists differ widely as to the nature of the right. Some maintain that it is ownership while others try to explain it as possession, that is, ownership of buildings, etc., or the possession of land. Both are wrong, for the ownership of land usually carries with it the ownership of whatever is attached to the land, and to recognize two sets of ownership on the same piece of land would not only be illogical, but might create unnecessary complications.
