On the 8th of the same month, the barometer was 30.05 at 8 P.M. with fine weather, wind South-East by East, it then commenced to fall, and at 8 P.M. on the 9th was 29.80, and blowing a heavy gale at South-East, which continued all night, and until 8 P.M. on the 10th, at which time it became more moderate, and the barometer began to rise.

What a different effect these gales had on the barometer; that from the North-West causing the mercury to fall nearly 6-tenths, whereas, the last, from South-East only lowered it 2-tenths, and 5-hundredths; they were of equal strength and duration, and both accompanied by heavy rain.

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ON THE NORTH-WEST COAST OF AUSTRALIA.

The great extent of the North-West coast of Australia, lying as it does between the parallels of 12 and 22 degrees of south latitude, no doubt subjects it to a variety of winds and weather, that is not experienced on the north coast; although, on that part of it north of the parallel of 15 degrees, there is probably much similarity.

As I cannot speak with certainty of the winds and weather that prevail on this extent of coast, at all seasons of the year, the following remarks will be confined to such portions of it as were visited by the Beagle, and will apply only to the particular seasons in which she was employed there.

To the eastward of the meridian of 123 degrees east longitude, and at a short distance from the land, the east and west monsoons will be found regular; but the easterly monsoon is very light to the southward of 13 degrees latitude.

Between Clarence Straits and Cambridge Gulf, and during the months of September, October, November, and December, the wind during the day is a seabreeze between North-West and West.  In September, and until the middle of October, we found the wind as follows:  About sunrise, a light breeze sprang up from South-East or East which gradually drew to the northward towards the middle of the day, in the afternoon, a seabreeze from North-West or west, becoming light towards sunset, but freshening again soon after that, and blowing a moderate and pleasant breeze between North-West and South-West all night.

During the latter part of the period (November and December) the winds were more constantly from the West or West-North-West, blowing from that quarter throughout the twenty-four hours, but much more moderate at night than during the day; at full and change of the moon, the breezes were much stronger than at other times, and upon one or two occasions, at the time of the moon’s quartering, there was a light breeze from South-East in the morning.

During the month of November, the ship was at anchor, twelve miles within the entrance to Victoria River, and sixty-five from Point Pearce, on the sea coast.  For the first three weeks of this time, the seabreeze was regular from North-West or West-North-West, generally setting in about noon, and lasting the greater part of the night; in the mornings, and until noon, it was mostly calm, or very light winds from the northward.  In the last week of this month the weather was very unsettled and squally, with much thunder and lightning, and rain, the wind mostly between South-East and North-East; after which, the westerly breezes set in again, and continued until we left the coast in the middle of December.