To the late Sir William Wilde belongs the honour of first drawing general attention to the water habitations of Erin; his labours have been ably followed up by W. F. Wakeman, who has so largely contributed to the _Journal of the Royal Historical and Archæological Association of Ireland_ both Papers and Drawings illustrative of the subject. In the present work, Kinahan, Reeves, Graves, Wilde, and other specialists, have been freely quoted, as evidenced in the text; in short, the observations of every author have been utilized, provided they touched on points that could tend in any degree to elucidate the subject under consideration. “A dwarf on a giant’s shoulders sees further of the two”: thus the writer, standing in this line of investigation on the eminence created by his predecessors, may perhaps be enabled to lay before his readers a distinct and comprehensive view of the Ancient Lake Dwellings in Ireland. Recent discoveries and new matter will be found in these pages; but the special intention has been to collect carefully all the information hitherto furnished by the explorers of Irish Lake Dwellings, and to present that information in a condensed form, “an abridgment of all that is pleasant,” so as to render it acceptable to archæologists, and perchance agreeable to the general reader, who, not having had his attention previously directed towards the subject, can scarcely be supposed willing to explore the voluminous records of scientific societies in search of items connected with the question of lacustrine remains in Ireland. This Publication may, perhaps, help to diffuse more generally the knowledge already possessed, so that when fresh discoveries are made in any new locality increased care may be devoted to the exploration; for every artificial island is not necessarily of remote antiquity, and the most careful examination is essential before arriving at a decision respecting the probable period of the primary construction of a crannog. It would be fortunate indeed should these pages excite sufficient attention to prove, even remotely, the cause of having the various relics indicative of the social economy and industries of the inhabitants of our ancient “water-towns” arranged systematically in the new Museum of the Science and Art Department, now in course of construction in Dublin. The facility thus afforded of studying these antiquities--some of them safely protected during untold centuries by their covering of peat and water--could not fail to lead to a clearer comprehension of the real condition of ancient culture and civilization in Erin. The Council of the Royal Irish Academy most generously permitted for this work the use of all the woodcuts in their possession illustrative of lacustrine remains, and the same favour was accorded by the Royal Historical and Archæological Association of Ireland, through the Secretary, the Rev. James Graves.