PACIFIC AND BEERING’S STRAIT. 
5 
had been observed by M. Dollond in another eclipse ; and as the sub- CHAP, 
ject has since received much interest from the circumstance of Aide- 
baran, and Jupiter and his satellites, having been seen projected upon 
the disc of the moon. About the time of the greatest obscuration, 
Leslie’s photometer stood at 27 exactly half what it afterwards 
showed. Between the intervals of observation, we amused ourselves 
with making experiments with a burning glass upon differently 
coloured cloths, in imitation of those recorded in the Correspondence 
of Baion de Zach, and which will convey to the general reader a more 
intelligible idea of the decrease of intensity in the sun’s rays at the 
time of the greatest obscuration, than the observations with the 
pho^ometei, as well as of the readiness with w'^hich some colours 
Ignite in comparison with others : for instance. 
^ Scarlet, Pea-Green 
burned instantly; required 3",7, 15'',7 : would not ignite. 
After the eclipse, and when the sun was shining bright, 
Blue, Scarlet, Pea-Green, Yellow, 
burned instantly; instantly; 2"; T's 8; 4", 3. 
The results are the mean of several observations ; and the intervals, the 
time between the rays being brought to a focus on the cloth, and its 
Ignition, 
trade-wind, we went through the usual ordeal of 
a ing winds and calms, with oppressively hot moist weather, and 
eavy rams ; and then, on the 19th, in latitude 5° 30 ' N., got the 
sout -east tra,de, with wLich we pursued our course towards the equator, 
and crossed it on the 24th, in longitude 30 ° 9 ! West, much further 
from the meridian of Greenwich than choice would have dictated. 
Some anxiety w^as in consequence felt lest the current, which here ran 
to the westward at the rate of thirty miles a day, should sweep the 
ship so far to leeward, as to prevent her weathering Cape St Koque 
the north-eastern promontory of the Brazil coast, and thus materially 
protract the passage, as it would be necessary to return to the variable 
winds about the equator to regain the easting, in consequence of the 
