The Bay of Fundy
If the tide-wave advances on a line at right angles to its front, we expect to find its front at right angles to the bay axisthat is, northwest-southeast. It appears that the wave does not advance up the Bay of Fundy because, drawing the iv h. 50 m. line with the utmost partiality to such a view, the greater part of its length in the Bay of Fundy trends northeast-southwest. In other words, the southern half of Nova Scotia seems to have almost no effect on the direction of the wave advanceor front, at any ratein the Bay of Fundy. Either the wave advances from southeast to northwest, which is not here supposable, or the tide in the main bay is not a progressive wave at all. The cotidals are drawn on the assumption of a progressive wave. The result is the reduction ad absurd of that assumption. The analysis of Mr Henry Mitchell t is in brief as follows : High tide occurs at about the same time from Labrador to Florida, except in the Gulf of Maine, where it is three and a half’ hours later. (1) A flood-current to southwest appears simultaneously along the whole outer coast preceding high water, which is followed by a general ebb-current to northeast; also appearing simultaneously along the whole coast. (2) Soon after high water outside, which is a time of level within the gulf, a current sets strongly to N. N.W. over the Sill into the Gulf of Maine and the water rises within the gulf. “An impulse observed at one of our current stations is almost immediately followed by a vertical change on the most distant shore.” The current continues to flow thus uphill until high water in the gulf, when it slacks and turns. Three hours later it is flowing, out with maximum strength, the gulf is level, and low water is established outside. While the water rises outside and the general flood-current of the coast sets to southwest, the gulf current continues to flow out over the Sill, again uphill, until three hours before high water without, when low water prevails in the gulf. (3) The water bodies move from top to bottom. A diver on the coast of Maine observed distinct motion in 23 fathoms.* Conclusion.The Gulf of Maine and Bay of Fundy offer a ” dead angle” to the general flood-current to southwest, while the ebb-current finds in it “a pocket into which the waters are crowded and, by virtue of their vis viva, piled up in the Bay of Fundy.” After comparing with a fluid oscillating in a bent tube with two arms of very unequal size and inclination, the author suggests that. the Bay of Fundy tides are a result of a rocking of the ocean into a contracting flume.