DEEP-SEA EXPLORATION. 
381 
Case I . — On April 28, 1883, single altitudes of the sun were observed at 6.43 a. m., 
8.47 a. ui., and 10.23 a. in., a sounding being taken at the time of each sight. The 
meridian altitude was observed at noon. The three time-sights were worked out for 
latitudes 35° 20' N. and 35° 30' N., jilacing the vessel respectively on the lines A A, 
B B, 00; and the meridian altitude placed her in latitude 35° 31' 35", D D. From the 
first sounding, ran 10 miles ESE. (mag.) to the second, where the temperature of the 
surface water and the current showed that the edge of the Gulf Stream had been 
reached. From the second to the third the drift in trawling and current was estimated 
at 3 knots NE. From the end of the third cast to noon the drift and current were 
about 2 miles NNE. These being iilotted, place the ship in the positions 1, 2, 3, 4. 
Case II . — While sounding at about 7 a. m.. May 1, a meridian altitude of the moon 
was observed, showing the latitude to be 36° 41' 05" N. At the same time a single 
altitude of the sun was observed and worked out for latitudes 36° 30' and 36° 40'. 
The ship was therefore at the intersection of the two lines thus found, A A, BB. 
While trawling, two more sights of the sun were taken, at 10.09 and 10.49; and being 
worked out with the same latitudes as before, placed the ship on the lines G C, D D. 
Finally a meridian altitude of the sun was observed, Avhich placed the ship in latitude 
36° 43' 54" at noon, EE. The drift while trawling, until the last time sight, was to 
NW., 2^ to 3 knots in all; and then, after the sight NW. by W. J W., 2-| miles to noon. 
No current noticeable. Plotting the track, the ship was found to have been in the 
positions 1, 2, 3, 4. 
Case III . — At 3 and 5.45 p.m., August 1, single altitudes of the sun were observed 
and worked out for latitudes 39° 40' N. and 39° 50', giving lines A A and B B. At about 
7.30 an altitude near meridian of * Antares was taken, which placed the ship at that 
time on the parallel of 39° 39' 23", line C O. The drift in trawling during the afternoon 
