Like most countries, the early traditions of Holland have been forgotten or ignored, and in its annals little mention is made of the _terpen_. In explanation of the origin and early use of the word, Dr. Pleyte quotes from Ocko van Scharl a passage to the effect that one of the ancient kings of Friesland, named Adgillus, who reigned towards the end of the sixth century, had caused, on account of the ravages of an inundation which took place four years prior to his accession, a large number of elevated places to be formed, so as to give shelter to man and beast in the event of a recurrence of this danger. These mounds were then called _Terpen_. Mr. Dirks, president of the Friesch Genootschap, as early as 1871 characterised these mounds as analogous to the terramara beds of North Italy ("_ce sont des terramares historiques_");[65] but it remained to Professor Pigorini of Rome to show that they were identical as regards internal structure. This he did in 1881 (B. 372c), after a visit to one at Aalzum which was then being excavated, when he showed that there was a circumscribing dyke, and, although no actual piles were then visible, he was informed by the proprietors that such wooden structures had been occasionally met with. Prior to his visit, it appears that no special attention was directed to these structural remains. From all he could learn, however, on this point, and especially from a consideration of the stratified arrangements of the _débris_, Pigorini concluded that the deposits were due to pile-dwellings, and had accumulated under precisely similar conditions to the terremare, in regard to which he is such a distinguished authority. The _terp_ at Aalzum is still being systematically excavated, and, though only as yet partially cleared off, its results, from an archæological point of view, are now second to none of the kind in Holland. Moreover, the excavations are conducted on an extensive scale, and the locality is readily accessible. I can, therefore, conceive of no better means of conveying to you some knowledge of the nature and structural phenomena of these remarkable deposits, than by detailing the facts which came under my own cognisance during a visit I made this summer to the same spot under the guidance of my excellent friend, Mr. Battaerd.