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intentionally; for after the trick put upon Mons. Labillardière at the Friendly Islands, in the words given him for the high numerals, they are always to be suspected.

During the week we remained in Caledon Bay, the following astronomical observations were taken.

The rates of the time keepers were found from morning's altitudes of the sun in an artificial horizon, between Feb. 3 and 8; and the means, with the errors from mean Greenwich time at noon there on the 9th, were as under:

No. 520 had been accidentally let down in Blue-mud Bay, whence its longitude is not now noticed; that given by No. 543 on Feb. 3, with the rate from Observation Island, was 136° 43′ 3″,5, or 7′ 16″ greater than the lunars. Were a rate used, equally accelerated from that of Observation Island to what was found in Caledon Bay, the longitude would be 0′ 55″ less than the lunars; but during the twelve days occupied in circumnavigating Groote Eylandt, it was proved that this time keeper was keeping its former rate, and consequently the acceleration cannot here be admitted.

In constructing the chart of the coast and islands between Pellew's Group and Caledon Bay, a time keeper was required only in laying down the south and east sides of Groote Eylandt, and the main coast up to Cape Barrow; in all the remaining parts the longitude was preserved by a connected chain of bearings, mostly taken on shore. The time-keeper reckoning from Observation Island, and