When this was finished, the azimuths of the line
for the two ends were computed, and marks were laid off for starting
with the line from both ends. One party, after cutting more than
forty-two miles through the woods, were agreeably surprised, on the
brow of a hill, at seeing directly before them a gap in the woods on
the next line of hill; it opened gradually, and proved to be the line
of the opposite party. On continuing the lines till they passed
abreast of each other, their distance was found to be 341 feet. To
form an estimate of the magnitude of this error, it is to be observed
that it implies an error of only a quarter of a second of time in the
difference of longitudes; and that it is only one-third (or nearly so)
of the error which would have been committed if the spheroidal form of
the Earth had been neglected. I must point out the extraordinary merit
of the officers who effected this operation. Transits were observed
and chronometers were interchanged when the temperature was lower than
19 deg. below zero: and when the native assistants, though paid highly,
deserted on account of the severity of the weather, the British
officers still continued the observations upon whose delicacy
everything depended.
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