Page:Proceedings of the Royal Society of London Vol 1.djvu/250

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The chief circumstance that induced Capt. Flinders to think his observations upon the marine barometer were worthy of attention, was the coincidence that took place between the risingand falling of the mercury, and the setting in of winds that blew from the sea. and from oﬂ’ the land, to which there seemed to be at least as much reference as to the strength of the wind or the state of the atmo- sphere.

Our author's examination of the coasts of New Holland and the other parts of the Terra Australis, began at Cape Leuwen, and con- tinued eastward along the south coast. His observations, which, on account of their length, we must pass over, show, that a change of wind from the northern half of the compass to any point in the southern half, caused the mercury to rise; and that a contrary change caused it to fall. Also, that the mercury stood considerably higher when the wind came from the south side of east and west, than when, in similar weather, it came from the north side.

Capt. Flinders now proceeds to relate the observations he made upon the east coast. From these it appears that the winds which came from between south and east caused the mercury to rise and stand high, as the same winds had done, with only one exception, on the south coast. The wind from north-east kept the mercury up above thirty inches on the east coast, and caused it to rise after all other winds, except those from the south-east ; whereas, on the south coast, those Winds caused the mercury to fall, and to stand much be- low thirty inches; owing, in our author's opinion, to the Wind coming from off the land. During north-west winds, the mercury stood lower upon both coasts than at any other time; and, on both, those Winds came from OH the land.

lVIoderate winds from the south-westward, with ﬁne weather, caused a descent of the mercury on the east coast; and during their continuance, it was much lower than with winds from the north- eastward; but upon the south coast it rose with south-west winds, and it stood much higher than with winds from the opposite quarter. But it must he observed, that the wind which blew from the sea upon one coast came from OH the land on the other.

The mean height of the mercury on the east coast is stated by our author to be not less than 30.08 or 30.10 inches; whereas upon the south coast he estimates its mean height to be 30 inches. The greatest range observed upon the east coast was from 29.60 to 30.36; while upon the south coast the range was from 29.42 to 30.51. But it must be remarked, that these extremes are taken for very short intervals of time.