^{page 23 note *} Sir S. Brown has indeed stated, that at Brighton he found the impetus of the waves during heavy gales was “equal to 80 Ib. to a foot upon a cylindrical column of 12 inches diameter.” The hydrostatical pressure of a wave only 1¼ foot high is equal to 80 Ib. upon a square foot.

^{page 24 note *} It has been suggested to me, that the indications of the instrument might be made through the medium of a flexible wire or chain at a considerable distance from the instrument, and thus the impulse of every wave might be observed.

^{page 25 note *} It was not thought necessary to give all the observations in the table appended to this paper.

^{page 26 note *} With reference to the continuous action of water, I may notice the effects produced by the failure of Beith's Dam, a reservoir situated upon the high grounds near Cartsdyke, immediately east of Greenock. This dam had a head of 20 feet of water, and gave way on the night of the 21st November 1835, when the water, after breaking down another reservoir below it, rushed through the streets of Cartsdyke, causing the melancholy loss of no fewer than 41 lives. This continuous flow of water carried away many houses; and, among other instances of its power, it is recorded that a “mass of rock about 16 tons weight was borne along by the torrent to a distance of 30 or 40 yards.” This case, then, which almost equals the records of the fury of the sea, shews the effects which continuous action may produce.

^{page 27 note *} At such a situation as the Bell Rock, a column of water or of air could be conducted into the interior of the house, and might, in the one case, shew the force of each wave as it struck the building by the rise of the water column; or, in the other, by a pressure-gauge, shew the same result in atmospheres by compression.