At Swan River, on the 24th of May, 1838, the wind was strong and squally from North-East by North; sympiesometer standing at 30.74. During the day the oil commenced to fall, and continued falling slowly until the 30th, when it was 30.16; during the greater part of this interval, the winds were light, generally from some eastern point in the morning, and going round the compass, by north and west, during the day; the nights were mostly calm, a heavy bank of clouds was collecting between North-North-East and South-West and the whole western horizon had a gloomy appearance. On the evening of the 30th, the water had risen considerably at the anchorage, and the stream ran to the southward; a fresh breeze also set in from North-East and gradually veered to the northward, as it increased in strength. On the 31st it blew hard all day, between North-North-East and North-North-West, with dark squally weather, much lightning in South-West and heavy rain, that continued all night. On June the 1st, the gale was at its height, and at 8 A.M. (the sympiesometer having fallen to 29.93) was blowing a hard gale, with heavy squalls and rain, from North-West; towards noon the wind veered to west, but still blew very hard; the sympiesometer now began to rise, and in the evening the wind was West-South-West and had moderated considerably, the weather was also clearer, although heavy clouds still hung on the western horizon.
The next morning (the 2nd) the sympiesometer had risen to 30.26; but this was much too sudden a rise (0.33 in 24 hours) to allow us to suppose, that the favourable change in the weather was to be of long continuance; during the day the oil began to fall again, and the wind veered to West and North-West and on the 3rd blew harder than ever, with heavy rain, thunder, and lightning; and, with the exception of occasional intervals, when the wind moderated, this weather continued until the 10th. The wind during this time was variable, between North-North-West and West-South-West, the sympiesometer between 29.81 and 30.16--falling with the North-West winds, and rising as the wind veered to west and West-South-West.
This gale, which may be said to have been of ten days' continuance, caused a very heavy sea upon the coast; the oldest residents at Swan River said they had never experienced so heavy a sea before. On the 10th the glass commenced to rise steadily, and the weather was fine, with light variable winds, until the Beagle sailed (on the 20th).
Owing to the security of Owen's anchorage, and the good quality of the bottom, the Beagle rode out this bad weather, without causing the slightest apprehension to anyone on board; but had a merchant vessel been in Gage Road, in all probability, she would have added one more to the list of wrecks, that have already done too much in prejudicing strangers against the Swan River settlement.
The gale of May, 1840, at Houtman's Abrolhos, commenced in a similar manner with that already described, but being in a lower latitude, was of shorter duration, and the indications did not precede it such a length of time; still they were in every respect similar.
This gale commenced on the 2nd of May, in the evening, and lasted until the evening of the 4th. on April the 29th, the barometer stood at 30.17 (having been some days steadily high); it then commenced to fall, and on the evening of May the 2nd, was 29.86; during this interval we daily experienced strong East-North-East and North-East winds; they generally commenced after midnight, and lasted until noon; a bank of clouds was also collecting in the North-West and there was occasional lightning in that quarter; the early part of May the 2nd was nearly calm, and there was a heavy bank of clouds between North and South-West. After noon a light breeze sprang up from North-West which gradually freshened; and during the night the barometer fell 17-hundredths.
At sunrise on May the 3rd, there was a fresh breeze from North-North-West and the weather had a very dull and gloomy appearance, the wind increasing rapidly, and by noon it blew a heavy gale at West-North-West; the barometer had fallen to 29.58, at which it continued until midnight, when the wind drew to the southward of west, and the mercury began to rise. The gale continued unabated, with squalls and rain, until noon of the 4th, although the barometer had been rising since the previous midnight; in the afternoon the wind moderated, and the weather became fine.
From this it would appear that the barometer gives ample warning of an approaching North-West gale, as it had been falling nearly four days before the commencement of the bad weather, this alone ought to be sufficient to put a man upon his guard if near the shore. Between April the 29th (the first day of the fresh north-easterly winds) and May the 3rd (when the gale was at its height, and the wind began to draw to the southward of west) the mercury had fallen 6-tenths. The change of current did not precede the wind, but changed with it; when the gale was strong from North-West and West-North-West the current ran a knot an hour to the South-East, and when the wind changed to South-West it ran with the same velocity to the North-East.
The west coast of New Holland is at times visited by sudden squalls, resembling hurricanes. I was told by the master of an American whaler, that in March 1839, when in company with several whalers off Sharks' Bay, he experienced some very bad weather, which came on suddenly, without having given any previous warning, but it was not of long continuance; the gusts of wind were very violent, shifting suddenly to all points of the compass. Some of the ships suffered considerable damage, in loss of topmasts, etc. others in sails, but all more or less. I think the first squall was from North-East off the land.
The American whalers that resort to the west coast of Australia, are upon different parts of it at all seasons of the year; their range is between the parallel of 10 and 50 degrees of south latitude. In the summer they fish to the southward, and at that season visit Swan River and King George's Sound, for refreshments; but during the winter months they are rarely to the southward of Sharks' Bay; numbers are to be met off the North-West Cape.