To a great extent, the redemption of all these lands will require extensive and comprehensive plans, for the execution of which aggregated capital or coöperative labor will be necessary. Here, individual farmers, being poor men, cannot undertake the task. For its accomplishment a wise prevision, embodied in carefully considered legislation, is necessary. It was my purpose not only to consider the character of the lands themselves, but also the engineering problems involved in their redemption, and further to make suggestions for the legislative action necessary to inaugurate the enterprises by which these lands may eventually be rescued from their present worthless state. When I addressed myself to the broader task as indicated above, I found that my facts in relation to some of the classes of lands mentioned, especially the coast swamps of the Gulf and some of the flood plain lands of the southern rivers, were too meager for anything more than general statements. There seemed to be no immediate necessity for the discussion of these subjects; but to the Arid Region of the west thousands of persons are annually repairing, and the questions relating to the utilization of these lands are of present importance. Under these considerations I have decided to publish that portion of the volume relating to the arid lands, and to postpone to some future time that part relating to the excessively humid lands. In the preparation of the contemplated volume I desired to give a historical sketch of the legislation relating to swamp lands and executive action thereunder; another chapter on bounty lands and land grants for agricultural schools, and still another on land grants in aid of internal improvements--chiefly railroads. The latter chapter has already been prepared by Mr. Willis Drummond, jr., and as the necessary map is ready I have concluded to publish it now, more especially as the granted lands largely lie in the Arid Region. Mr. Drummond’s chapter has been carefully prepared and finely written, and contains much valuable information. To the late Prof. Joseph Henry, secretary of the Smithsonian Institution, I am greatly indebted for access to the records of the Institution relating to rainfall. Since beginning my explorations and surveys in the far west, I have received the counsel and assistance of the venerable professor on all important matters relating to my investigations; and whatever of value has been accomplished is due in no small part to his wisdom and advice. I cannot but express profound sorrow at the loss of a counselor so wise, so patient, and so courteous. I am also indebted to Mr. Charles A. Schott, of the United States Coast Survey, to whom the discussion of the rain gauge records has been intrusted by the Smithsonian Institution, for furnishing to me the required data in advance of publication by himself.