From this view of the time-keeper it appears, that for near two years it altered its rate very inconsiderably, and therefore that its error, according to the Greenwich rate, if we had had no opportunities of correcting it, amounted only to 2-1/4 deg.. That afterward, at King George's Sound, or Nootka, it was found to have varied exceedingly; of course, the longitude, by its Greenwich rate, was becoming considerably erroneous. About this time, it should be remarked, the thermometer was varying from 65 deg. to 41 deg.. The greatest alteration we ever observed in the watch was, during the three weeks we were cruising to the N.; in which interval, it gave the longitude of the East Cape with a difference of twenty-eight miles, I have marked the longitude of Saint Peter and Saint Paul, as given by the time-keeper, notwithstanding it stopped a few days before we arrived there; this I was enabled to do, from comparing the longitude it gave the day before it stopped, with that given by Mr Bayley's watch, and allowing for the error of the latter. The use of so accurate a measure of time is sufficiently evident, from its furnishing in itself the means of approximating to the longitude at sea, as may be seen in the above table. But, besides this, we were enabled, by the same means, to give a degree of accuracy to the lunar observations, which they cannot otherwise pretend to; and, at the same time, by reducing a number of those observations to one time, obtain results approaching still nearer to the truth. In surveying coasts, and ascertaining the true position of capes and head-lands, it reaches the utmost degree of practical exactness. On the other hand, it is to be observed, that lunar observations, in their turn, are absolutely necessary, in order to reap the greatest possible advantages from the time-keeper; since, by ascertaining the true longitude of places, they discover the error of its rate. The original observations that were made in the course of this voyage, have been published by order of the Board of Longitude, and to those I must refer the reader, for his further information on this subject. N.B. The observatories were placed on the west side of the village of Saint Peter and Saint Paul. Latitude deduced from meridian zenith distances of the sun, and of five stars to the S., and five to the N. of the zenith 53 deg. 0' 38" N. Longitude deduced from one hundred and forty-six sets of lunar observations 158 43 16 E. Longitudy by time-keeper, according to its Greenwich rate 173 36 0 Longitude by time-keeper, according to its rate found at Owhyhee 159 20 0 Variation of the compass, by azimuths taken with three compasses, made by Knight, Gregory, and Martin 6 18 40 E. Dip of the North Pole of the magnetic needle, being a mean of the observations taken in June and September 63 5 0