"The continental systems were the outgrowth of the civil law, which, without exception, furnished the basis of the laws of nearly every country in Europe outside of Great Britain, and to some extent there. Naturally, therefore, their systems followed the principles of the civil law, by which it was established that the ownership of all was primarily vested in the State, and that all mines of gold or silver in public lands belong to the state or sovereign, as a part of the sovereign patrimony, whence it followed that the right of severance could be exercised, and the minerals granted to one and the land to another, or the land and minerals together. But in private lands, closely analogous, to the rule of the common law, and probably the foundation of it, the minerals belonged primarily and prima facie to the owner of the soil, with this condition or limitation, similar to the rule prevailing in Russia, that if worked by the owner he was bound to render the tenth part to the sovereign as a right attaching to the crown; and if worked by another with the consent of the owner, there was a fixed and standing royalty of one-tenth to the crown and one-tenth to the owner.6 "By the rule of the common law from the earliest time, prima facie and as a general rule, the owner of the soil owned all beneath it, with the limitation only- the burden of showing which was upon the person attempting to rebut the presumption of ownership- that 'Royal mines' belonged to the crown or sovereign. By some of the earlier statutes and decisions there was some doubt as to what was included in the term 'Royal mines,' the attempt being made to include copper and tin as well as gold and silver; and by others a distinction was sought to be made between the values of baser metals and those of gold and silver. This, however, was virtually settled by the statute of William and Mary,7 by which it was ordained that the enjoyment of all mines in which tin, copper, iron or lead were found, notwithstanding any quantity of the precious metals intermixed, was secured to the subject." 8 9