Can be entered by preëmption upon proof that mines or minerals are not contained therein. Lands found, after entry as agricultural, to contain valuable mineral deposits, such entry will be cancelled. Where, however, a patent has issued, and the land has been afterwards found to embrace a valuable deposit or lode, the title is valid, as the land has ceased to be part of the public domain. Proof, however, that the deposit, lode or mine was known before the patent issued will invalidate title thereto. Titles to town sites and lots are held subject, also, to mineral rights, which remain in the United States. Under Act of 1876, it was permitted to any person, under the limit of citizenship, or declaration of intent, to proceed upon the public land, and occupy such area, to the extent of one section, or 640 acres, which cannot be cultivated or used for agricultural purposes, with the artificial conveying of water thereon and irrigation; three years being given to construct the necessary works and improvements. The price of such land is to be $1.25 per acre, one-fifth being required to be paid at the time of location. In consequence of doubt as to the character of land which this act was designed to embrace, and charges made of fraudulent entries, further legislation will doubtless be had on this subject. Coal lands are allowed to be entered in legal subdivision parcels, not to exceed 160 acres to any one person, or double that quantity to an association; the price of the same to be $20 and $10 per acre, according to whether or not the same be located within fifteen miles of a completed railroad. Rivers are deemed navigable only when they are used, or are susceptible of being used, for commercial highways. The shores and soil under them were reserved to the States respectively, and new States have the same jurisdiction and sovereignty as old ones. The Land Office has never permitted a complication of such rights by attempting or permitting the sales of any portion of the beds of said rivers or streams. Saline lands are not subject to homestead or preëmption entry. This policy has been uniform since the beginning of our land system. The Supreme Court has held uniformly that Congress has uniformly designed to prevent the sale of saline deposits and springs. The existence of such deposit or spring withdraws any quarter or other large portion of a section from settlement and location. United States Land Office Fees. United States Land Office Registers and Receivers are permitted by law to charge the following fees: