270 
GREENLAND VOYAGE. 
I took a sketch of the whole visible coast, and the 
hearings of every remarkable headland, bay, and 
mountain. The northern limit of the particular 
survey made on the 20th of July, was now the 
most southern object in view, bearing very nearly 
due south: this fortunate position of a point of 
land determined twenty-five days before, enabled 
me, not only to connect the two surveys, indepen¬ 
dently of the chronometrical observations now ob¬ 
tained, but also to correct the rate of my chrono¬ 
meter. The longitude of the ship, determined 
by the bearing of the land, was 21° 22' W., and 
by the chronometer, 21° 42' 30" W. This diffe¬ 
rence of 20' 30" arose from the error in the origi¬ 
nal rate of the instrument, which was not at this 
time exactly known; but it was subsequently com¬ 
pensated with all possible care, and the observa¬ 
tions for longitude given throughout this volume 
corrected. The variation, by the mean of two 
sets of observations, appeared to be 43° 22' W. 
The first set gave 43° 20', and the second 43° 24'. 
The coast now in sight was nearly ninety miles 
in extent, north and south, of which, by the aid 
of observations made on the 26th of June, and on 
the 8th, 12tli, 17tli and 20th of July, I was ena¬ 
bled to obtain a very good survey. 
From a point of land, in latitude 71° 14', the 
northern limit of the survey accomplished on the 
