On the Evidence of Certain Phenomena, &c. 313 
the Society Islands. On the southern coast of the United States, 
and at the island of Bermuda, in the Atlantic, it is high water about 
seven o'clock, the flood tide in the offing at the latter place running 
to the northeast. On the southern coast of Rhode Island and Massa- 
chusetts, it is high water from seven to eight o’clock. On the south- 
eastern coast of Nova Scotia and Newfoundland, it is high water 
from eight to nine o’clock, the flood tide off the latter coast also run- 
ning northeastwardly. At the Azores, or Western Islands, in lat. 
38° N., near the middle of the Atlantic, it is high water about 12 
o’clock, and the flood runs to the eastward.* Finally, it is high wa- 
ter on the western coasts of Ireland and Spain about two o’clock,— 
all on the same days. ‘These statements are approximated from 
the American Coast Pilot, and other authorities, care being taken 
to avoid the retarding effects of local obstructions as far as possible, 
by timing from tue most extraneous positions of coast, towards the 
open ocean. 
Viewing these phenomena in connexion with some other facts, I 
was led to suspect that the great tide wave performes an actual cir- 
cuit in each of the great oceanic basins, on both sides of the equator, 
passing westwardly in the equatorial latitudes, and returning east- 
wardly in the higher latitudes, above 25° or 30° N. and S., and analo- 
gous to the course which is pursued, as can be demonstrably shown, 
by the great currents, both of the ocean and the atmosphere. Ifsuch 
be the operation of the tides, certain regions in mid-ocean would 
form the foci, or neutral points, in these great elliptical circuits, and 
would be but slightly, if at all, affected by the ordinary tides. The 
elaborate investigation of cotidal lines in which Professor Whewell 
is engaged, will probably show whether this conjecture is well found- 
ed, or whether the course of the great tide wave be from the Southern 
Ocean, northwardly, through the entire length of the Atlantic, and 
in disregard of the direct lunar influence in this ocean, as would 
seem to be indicated in his Jate paper on that subject. ‘The greatest 
difficulty attending the inquiry, is in procuring correct observations 
from those islands and external points of coast, which bear most de- 
cidedly upon the question; and whatever may be its results, I am 
happy to find that a course or method of investigation which has 
governed my own inquiries in meteorology, has been adopted on this 
kindred subject, by so able an investigator. 
* See Penny Cyclopedia; article, Azores. 
Vou. XXVIII INO we: 40 
i 
