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 N. W., and at 8.00 the shift came, in force from 7 to 9 from W. N. W. $1⁄2$ W. with a re-appearance of heavy rain and violent squalls; the barometer had risen to 28.32. At 9, the wind was W. by N. barometer 28.70, showing a rise of 0.38 inch during the hour; the wind blew with a force of from 8 to 10. At 10 the wind was nearly W., force from 4 to 6; barom. 28.93, showing a rise of 0.23 during the hour; the rain at this time ceased. At 10.15 the blue sky appeared; and at 11 the typhoon had entirely passed away, and the barometer had risen to 28.99.

This diagram shows the centre to have passed over this place, and this is made evident (in accordance with the law) by the wind remaining nearly stationary during the first half of the gale, a thing which can only occur when the centre is travelling directly towards you, or when running on a course parallel to the course of the “Typhoon”—keeping the bearing of the centre the same as with the bearing of the centre, the wind must always change.

Take for an example this typhoon travelling N.E. instead of N.N.E., or at an angle 22$1⁄2$° to the first line of bearing of the centre as observed at the beginning of the Typhoon—the centre in that caxc would not have passed over Yokohama but about 20 miles to the Eastward, and the winds would have changed as follows: commencing at 4°° E.S.E.—as it was—at 5°° wind would have been E. by S., at 6°° E.N.E., at 7°° N.N.E. nearly, at 8°° N. by W. $1⁄4$ W., and at 9°° N.N.W. $1⁄4$ W., at which time the storm-circle would have left us, and we should have passed through the cord of an are equal to 138° of the storm circle, and the length of that cord would have been equal to about 98 miles. I have computed the diameter of this typhoon to be 105 miles, the whole diameter requiring seven hours to pass a given point, travelling at the rate of 15 miles an hour. The diameter and rate of travelling is arrived at by knowing the time occupied in passing over a space of 15 miles from a point in the vicinity of Cape Kamisaki to the Idaho’s anchorage in this harbour.