192 Mr. Rennell's Observations on a Current 
an error in the log, or even in the position of the needle 
point on the Isle of Wight, from whence the departure was 
taken ; but it may also be owing to the westerly current, 
whilst the ship remained in it, on the 27th ; if we admit that 
such a current prevails at all times, though in different de- 
grees of strength. Here it is proper to remark, that in deli- 
neating Captain Cooper's track, on the chart, I have scrupu- 
lously adhered to the result of each day's work, of the reckon- 
ing, as I find it in his journal ; contenting myself with in- 
serting my own observations on the track, in this paper 
only ; where they cannot mislead. 
The longitudes pointed out by the time keepers on the 
28th, 29th, and 30th, shew, that the increasing, though 
trifling differences, between the true longitude, and that by 
the dead reckoning, had amounted to 24 minutes only, on the 
30th. At this time the ship was about 24 leagues to the 
WSW of Scilly ; and, at 5 or 6 leagues to the SSE of this 
position, (that is, at 25 leagues SW by W from Scilly) they 
had soundings at 70 fathoms. This last particular is men- 
tioned, to prove that the longitude shewn by the time 
keepers (8° 28' west from London) was nearly the longi- 
tude in which the ship really was, on the 30th of January. 
That of St. Agnes (Scilly) is taken at 6° 46'. 
The Atlas was now entered into the stream of the same 
current which occasioned so much delay to the Hector ; 
but the course of the Atlas, being opposite to that of the 
Hector, it facilitated her progress ; and also carried her clear 
of the south-west coast of Ireland. 
On the 31st, the time keepers shewed that the ship had been 
set very considerably to the westward of the reckoning ; and by 
