AFRICA. 37 
The ordinary duration of this kind of 
ftorm is three days : fomethiies It continues, 
without remifiion, for a much longer fpace 
of time ; often, alfo, it ceafes fuddenly ; and 
during the three months when it prevails, if 
it happen to ceafe feveral times in this man* 
ner, it is a fure fign that great ficknefs will 
follow. 
Though this wind is not abfolutely dange- 
rous for lliips, there have been more than one 
inftance of its incommoding a great many. 
When it is too impetuous, from prudence, 
and to avoid even the fear of an accident, 
they make f9r the open fea ; but, when it col- 
le£t:6 no fog, it is not perceived in the tov/n, 
and blov/s only in the road. It is therefore 
the accumulation of the fog, which, moving 
forv/ard with great velocity, occafions tliefe 
dreadful hurricanes. Very often it is irapof- 
fible to crofs the ftreets; and, notwithftanding 
the care and attention with which doors and 
Vv4ndov7S are (hut, the duft penetrates even into 
trunks and dicfts of drawers. But, however 
inconvenient this vv^ind may be, it ftill procures 
great advantages to the town ; it frees it from 
mephitic vapours^ occafioned by the filth v/ hich 
