THE LOWS
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(especially of Statice bmervosa), this stony desert clothes itself in August with sheets of purple visible from afar.
   The lows separating the dune ranges differ from ordinary valleys in that they have never been excavated from a previously continuous terrain. They are gaps left from the first in the system of construction. The best example is Long Low, running from the Life-boat House to the north-west of the huts and to the south-east of the Laboratory. It dies out towards the Bend some three-quarters of a mile from its point of origin. Two hundred yards north-east of the Laboratory it is blocked by a bridge of sand blown from an adjacent dune. Glaux Low lies just north-west of the Laboratory, and can be followed for a distance of nearly half a mile in a north-east direction, where it communicates with Long Low (Plate XXII, lower picture). In the direction of the Life-boat House it has been long practically obliterated by blown sand, excepting the south-west extremity which is still open. Seaward of Glaux Low is Great Sandy Low, the dominating feature of the topography on the outside of the Headland (PI. IV, 2, p. 58). This low is essentially a long bay of some ten acres penetrating the heart of the dunes. Into Great Sandy Low the spring tides flow, and the very highest (not more than one or two a year) reach the north-east parts of Glaux and Long Lows. Owing to sand blockages the south-west parts of these lows are inaccessible except on the rarest occasions. Thus, the end of Glaux Low by the Laboratory has been reached by the tide only twice in the years 1913-6, whilst Long Low, from the sand block to the Life-boat House, was invaded by the tide on 14th September, 1916, for the first time since November, 1897. From an engineering point of view these lows are of considerable interest, because they afford lines of access for the sea. Theoretically, each low should be an isolated valley, but as a matter of fact the sea has established points of connection between them, as a study of the ground or of the map (fig. 50, p. 221) will show. As the floor of the low is commonly appreciably below the level of the point of ’entrance by the sea, the tide pours in with a tremendous rush, undercutting the sides and lowering the floor. In this way every tide makes it easier for the next one to gain access, and in the
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