Notwithstanding the striking and singular appearance the Swiss lake-dwellings must have presented to foreigners and strangers, it is a remarkable fact that Roman writers are entirely silent about them. Nor can this silence be accounted for on the supposition that the lake-dwellings had entirely come to an end prior to Roman times, as several of them have furnished antiquities whose Roman origin cannot be mistaken. Some archæologists think they recognise in the representation of a Dacian village on the Column of Trajan a true pile-village (B. 164); but this is doubtful, and, even if true, it is but a very meagre evidence of the custom, and leaves the problem of the lake-dwellings as mysterious as ever. Such reticence on the part of classical writers does not, however, extend to the class of ancient remains I am now about to describe. Pliny very distinctly states that the Chauci (Frisians and other races along the coast of the German Ocean) were in the habit of constructing artificial mounds, on which they built their houses so as to be beyond the influence of the waves and tides. The following passage from his "Natural History"[64] will be read with interest in relation to the recent discoveries that have been made in the localities referred to. "I have myself personally witnessed the condition of the Chauci, both the Greater and the Lesser, situate in the regions of the far north. In these climates a vast tract of land, invaded twice each day and night by the overflowing waves of the ocean, opens a question that is eternally proposed to us by Nature, whether these regions are to be looked upon as belonging to the land, or whether as forming a portion of the sea?