In the other letters written in 1685 and 1686 he applies to Flamsteed for information respecting the orbits of the satellites of Jupiter and Saturn, respecting the rise and fall of the spring and neap tides at the solstices and the equinoxes, respecting the flattening of Jupiter at the poles (which, if certain, he says, would conduce much to the stating the reasons of the precession of the equinoxes), and respecting the difference between the observed places of Saturn and those computed from Kepler's tables about the time of his conjunction with Jupiter.
At neap tides to 25 ft.
On the other hand, Pelvetia canaliculata, which marks the upper belt, is exposed for longer periods, and during neap tides may not be reached by the water for many days.
Is sometimes exceeded; the average neap rise is 282 ft.
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.