About the time of the maxima there must be a longer tidal range (that is, a greater rise and fall than the average); the difference between neap tides and spring tides will also be increased, and as results of these conditions there must be great tidal floods breaking over lowlying coasts and producing extensive denudation.
Abbe showed that for the production of an image the diffraction maxima must lie within the exit pupil of the objective.
In most cases two distinct maxima and minima occur in the 24 hours.
And intended to eliminate irregular changes, but they also to some extent eliminate regular changes if the hours of maxima and minima or the character of the diurnal variation alter throughout the year.
The 12-hour term is much less variable, especially as regards its phase angle; its amplitude shows distinct maxima near the equinoxes.