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 Idaho (or any other given point); and the time occupied by the semi-diameter in passing, 3$1⁄2$ hours.

During the first hour the fall of the barometer was 0.14 of an inch, during the second hour 0.20, during the third hour 0.44, and during the remaining 30 minutes 0.21, showing, in this instance, a proportion of fall, by comparison of the third with the first hour in the ratio of 1 to 3; and the distance from the centre being 52$1⁄2$ miles when the fall of the barometer was 0.14 of an inch per hour, agrees nearly with Mr. Peddington’s estimate of the distance with a corresponding fall of the barometer, his distance being 50 miles, with an average fall of 0.15 per hour.

I infer from this that the distance of the centre in a typhoon from any part of it may be calculated approximately by this method, providing the observer is on shore, has a good barometer, and watches it closely.

The total fall of the barometer during the typhoons on record ranges from 1.00 inch to 2.70 inches; the latter in the case of H. E.I.C. S. “Duke of York” off Kedgeree in 1833, from 29.00 to 26.30 inches.

The ship Argyleshire, here represented in a typhoon, was making a passage from Hongkong to Yokohama, and on the 11th of September was near the South end of Formosa, Betel Tobago bearing N.E., 23 miles. She was struck by a Typhoon with the wind at N.N.E. and the centre bearing E.S.E., and the captain believing the gale to be travelling to the Northward, supposed himself to be in the left hand semicircle, and continued on the port tack heading to the Eastward as near his course as possible, thinking all the time the centre would pass to the Northward of his ship ere he could approach sufficiently near to be in any danger. He evidently had an eye to business, and judging from the manner in which he handled his ship afterwards that he was conversant with the Law of Storms, I am of opinion that he desired to approach the