V0\ 
iSouik Coast. 
CHAPTER XI. 
Of the winds and currents on the south coast of Terra Australis, and in 
Bass' Strait. Usual progress of the gales. Proper seasons for sailing 
eastward, and for going westward : best places of shelter in each case, 
with some instructions for the Strait. 
Before entering upon the second part of the voyage, it seems 
proper to give an account of the winds and currents which prevailed 
upon the South Coast; and to add thereto such other general in- 
formation as may be useful in rendering the navigation more safe 
and expeditious, both along the coast and through Bass' Strait. 
The rate and direction of the currents here described, are 
deduced from the daily positions of the ship by astronomical observ- 
ation, compared with those given by a log kept in the common way, 
but with somewhat more than common attention. In the observa- 
tions, however, there may be some errors, and a log cannot be 
depended upon nearer than to five miles in the distance, and half a 
point in the course for the twenty-four hours ; and consequently this 
account of the currents must be taken as subject to the sum, or to the 
difference of the errors in the observations and log; though it is 
probable they may have been diminished by taking the medium of 
several days, which has always been done where it was possible. 
Besides the difficulty there is in obtaining the exact rate and 
direction of a current, it is known that a continuance of the wind in 
any particular quarter may so far change its rate of moving, and 
even its direction, that at another time it may be found materially 
different in both. Of the probability of these changes the com- 
mander of a ship must form his own judgment, from the winds he 
