This is afforded, either by means of a so-called sleeping dike (slaperdyk) behind the weak spot, as, for instance, between Kadzand and Breskens in Zeeland-Flanders, and again between 's Gravenzande and Loosduinen; or by means of piers or breakwaters (hoofden, heads) projecting at intervals into the sea and composed of piles, or brushwood and stones.
During the 13th and 14th centuries the castle and lordship changed hands very frequently; they were granted successively to Hubert de Burgh, whose son forfeited them after the battle of Evesham, to Richard, earl of Cornwall, whose son Edmund died without issue; to Piers Gaveston, and lastly to John of Gaunt, duke of Lancaster, and so to the Crown as parcel of the duchy of Lancaster.
Formerly when bridge piers had to be placed where a firm bearing stratum could only be reached at a considerable depth, a timber cofferdam was used in which piles were driven down to the firm stratum.
A broadside entitled Davy Dycars Dreame, a short and seemingly alliterative poem in the manner of Piers Plowman, brought him into trouble with the privy council, but he was dismissed with a reprimand.
Jak Upland (John Countryman) took the place of Piers Ploughman, and upbraided the clergy, and especially the friars, for their wealth and luxury.
Two of the tower piers and a part of one arch give some indication of the grandeur of the building.
The bases are either grouted with cement, or bolted to the foundations, but where cast column bases rest on masonry piers or footings any considerable grouting is not advisable.
Hoy is commonly approached from Stromness, there being piers at n Linksess, the nearest point to Graemsay, and at Hackness, South Ness and North Bay, the last three all on the harbour of Long Hope.
The piers of the Benares bridge were single iron caissons, 65 ft.
The intermediate piers should also have considerable stability, so as to counterbalance the thrust arising when one arch is loaded while the other is free from load.