“FORESHORE”
 27
Court decision as those “between high- and low-water marks of ordinary tides”, the basis of survey appears to have been modified. The Director-General points out that although in a given locality high-water line might remain constant the simultaneous position of low-water line might fluctuate, causing, as the case might be, a steepening or flattening of the gradient of the shore, which in its turn would affect its area. In estimating the aggregate gain or loss due to accretion and erosion the question of the inclusion or exclusion of the foreshore constitutes an important and precarious factor, as, if the foreshore be excluded and the area of terra firma only be considered, obviously this element of uncertainty would be to a large extent eliminated. The Ordnance Survey authorities 'were in fact faced with the primitive dilemma as to what constitutes land and what water. Moreover, in many instances land reclamation was carried out, increasing the area of the soil of Great Britain by artificial means. Mean sea-level is the most reliable datum in respect of plotting the contours of tidal range, and on Ordnance maps it is stated that the altitudes are given in feet above the assumed mean level of the sea at Liverpool, which is 0.650 feet below the general mean level of the sea. Apparently until 1913 mean sea-level was not ascertained with accuracy. It would appear, therefore, to be legitimate to take the official statements with regard to the estimated increase in land area of the kingdom with considerable qualification. The recommendation of the Commission under this head is as follows:—
   “ It would be of advantage if the Ordnance and Geological Surveys could take steps to ascertain from time to time whether, and, if so, to what extent, changes in the relative levels of land and sea are taking place
   Arising out of a recent case, a paper read before the Law Society1 is of interest. It may perhaps be noted that the Ordnance Survey Department relies upon the case of Attorney-General v. Chambers for a definition of the term “foreshore”. In this case the coastal area overflowed by the average of
     1 "The Foreshore" (J.W. F. Jacques), Law Society’s Birmingham Meeting, iqo8. (Spottis-woode & Co.)