Page:A Voyage to Terra Australis Volume 1.djvu/272

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island Amsterdam, the winds were never so strong as to reduce the Investigator to close-reefed top sails; and on the other hand, the calms amounted to no more than seven hours in nineteen days. The average distance on the log board upon direct courses, for we had no foul winds, was a hundred and forty miles per day; and the Investigator was not a frigate, but a collier-built ship, and deeply laden. In the following twelve days run, from Amsterdam to the south-west cape of New Holland, the same winds attended us; and a hundred and fifty eight miles per day was the average distance, without lee way or calm.

On the 12th, I took the opportunity of light winds to send down a bucket, fitted with valves to bring up water from a depth; but having no thermometer of a proper size to go into the bucket, I could only immerse one after the water was brought up. In this imperfect way, the temperature at 150 fathoms depth was found to be 63°,1, differing very little from that of the water at the surface, which was 69°,8. In the air, the thermometer stood at 63°,6. The specific gravity of the water brought up was afterwards tried at King George's Sound, and proved, at the temperature of 69°, to be 1,026, taking that of the crystal-glass bulb, with which the experiment was made, at 3,150; and the specific gravity of the surface water, taken up at the same time, was exactly the same. The latitude of our situation was 36° 36′ south, and longitude 38° 23′ east. The mean inclination of the dipping needle, placed upon the cabin table, was 58° 4′ of the south end; and the variation, by mean of azimuths on the preceding evening and amplitude this morning, taken on the binnacle when the ship's head was S.E. by E., magnetic, was 31° 47′; but the true variation, or such as would have been obtained with the head at north, or south, I consider to have been 29° 22′ west.

Throughout the passage to the island Amsterdam, we were accompanied by some, or all of the oceanic birds usually found in these latitudes; but not in the numbers I had been accustomed to