Having received orders the next day to go to Bolcheretsk, the time-keeper was left in the care of Mr Bayley, to compare it with his watch and clock, in order to get its rate. On my return, I was told it had gone for some days with tolerable regularity, losing only from fifteen to seventeen seconds a-day, when it stopped a second time. It was again opened, and the cause of its stopping appeared to be owing to the man having put some part of the work badly together when he first opened it. Being again adjusted, it was found to gain above a minute a-day; and, in the attempt to alter the regulator and balance-spring, he broke the latter. He afterward made a new spring; but the watch now went so irregularly, that we made no farther use of it. The poor fellow was not less chagrined than we were at our bad success; which, however, I am convinced, was more owing to the miserable tools he was obliged to work with, and the stiffness his hands had contracted from his ordinary occupation, than to his want of skill. For the satisfaction of those who may wish to have a general view of its rate of going, I have added the following table. The first and second columns contain the dates when, and the names of the places where its rate was observed. The third column contains the daily error of its rate, so found from mean time. The fourth column has the longitude of each place, according to the Greenwich rate; that is, calculated on a supposition that the time-keeper had not varied its rate from the time it left Greenwich. But as we had frequent opportunities of ascertaining the variation of its daily error, or finding its new rate, the fifth column has the longitude according to its last rate, calculated from the true longitude of the place last departed from. The sixth is the true longitude of the place deduced from astronomical observations made by ourselves, and compared with those made by others, whenever such could be obtained. The seventh column shews the difference between the fourth column and the sixth in space; and the eighth the same difference in time. The ninth shews the number of months and days in which the error, thus determined, had been accumulating. The difference between the fifth and sixth columns is found in the tenth, and shews the error of the time- keeper, according to its rate last found, in space; and the eleventh the same error in time. The twelfth contains the time elapsed in sailing from the place where the rate was last taken, to the place whose longitude is last determined. The thirteenth and fourteenth contain the state of the air at the time of each observation. As persons, unaccustomed to calculations of this sort, may find some difficulty in comprehending the nature of the table, the two following instances will more clearly explain it.