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turtle at that time. For a similar expedition from the opposite part of the South Coast, September, October, and November would seem to be most proper.

From the time of first arriving, to that of quitting Sweers' Island, the range of the thermometer on board the ship was between 81° and 90°, and on shore it might be 5° to 10° higher in the day time; the weather was consequently warm; but being alleviated by almost constant breezes either from sea or land, it was seldom oppressive; and the insects were not very troublesome. The mercury in the barometer ranged between 30,06 and 29,70. It stood highest with the winds from the sea, between north-east and north-west; and lowest when they blew gently off the land, between south-east and south-west, but most so from the latter direction. On the South Coast the winds from these points had produced a contrary effect: the mercury there stood lowest when the northern winds blew, and highest when they came from the southward; they coincided, however, so far, in that the sea winds raised, and the land winds depressed the mercury, the same as was observed at Port Jackson on the East Coast.

The rates of the time keepers were deduced from morning's altitudes, taken with a sextant and artificial horizon at the shore under Inspection Hill, from Nov. 16 to 29; and the mean rates during this period, with the errors from mean Greenwich time at noon there on the 30th, were as under:

The longitude given by the time keepers, with the rates from Upper Head in Broad Sound, on our arrival Nov. 16, was by