addition of larger sizes in the area of the inlet mouth, then the weak 
trend of slightly larger sizes associated with the breaker zone would have 
been expected to continue from the vicinity of the pier to an intersection 
with the "peak" of highest values near the breaker zone, i.e., at the +0.1 
contour. 
As to the limit ofinfluence of the inlet mouth on nearshore bottom 
changes in mean particle size, we returned to the quadratic trend surface 
for an experiment in finding this limit to a first approximation. Use of 
the quadratic surface rather than the cubic was in part dictated by our 
approach, which is described in the next section. As a closing remark on 
the cubic surface and its deviation map, we may conclude the sum of squares 
discussion with the following summary: 
Percent Percent Sum 
Sum of Squares of Squares of 
Attributable to Deviations From 
Surface Surface the Surface 
Linear ikl 3} 88.7 
Total Quadratic 47.7 52.3 
Total Cubic 59.6 40.4 
Thus, there still remains 40.4 percent of the total map variability 
in mean grain size in the deviations from the cubic. Moreover, the con- 
tribution of the "pure" cubic alone is only 11.9 percent, as against the 
36.4 percent attributable to the "pure" quadratic. The linear contribu- 
tion, as was stated, is 11.3 percent, implying that the total quadratic 
component is perhaps the most important one in the complete trend. In our 
study of the limit of inlet influence then, we take the cubic and higher 
order trend components as being merged with the local, non-systematic 
fluctuations that may be present, and return to the total quadratic 
surface of Figure 11 for further discussion. 
THE AREA OF INLET INFLUENCE ON MEAN PARTICLE SIZE 
Figure 11 contains two sets of contour lines of mean particle size. 
The heavy lines parallel to the shore represent a portion of the quadratic 
surface fitted to the sample data obtained from the three transects of 
Figure 5, which were mentioned earlier in passing. This surface for the 
whole beach area accounts for only 6.6 percent of the total sum of squares 
of mean particle size from all samples from the three transects. 
Inasmuch as the map based on the three transects does not include the 
sampling points in the immediate vicinity of the inlet (except for the pier 
samples on the left of Figure 6), this map represents the large-scale 
