30 
SURVEY OF THE INTERTROPICAL 
Isis, two and a half fathoms, at about a quarter of a 
Feb. 19. mile from the shore. 
20. The following morning, we ascended it in a boat 
for four miles. On our way to the entrance, which 
was between the reef and the shore, we had some 
difficulty, even with the boat, in finding a chan- 
nel; but when we were within the heads, we 
found a regular depth of from ten to twelve feet: 
the banks on either side were, for two miles, im- 
penetrably lined with mangrove bushes, which 
bore the marks of having been torn down by 
freshes or inundations. Beyond this the banks 
were low and sandy, but the channel of the river 
was of mud. At high water we landed to ex- 
amine the country, and ascended a sand-hillock, 
the only elevation we could find, to procure a 
view around ; it was so low that our prospect 
was very limited, yet still it was sufficient to 
satisfy us of the aridity and poverty of the soil : 
the country bore the appearance of having been 
under water, which seemed to be occasioned by 
high tides, for there were large patches of salt 
incrustations, which could only have been caused 
by an inundation of sea-water. Two or three 
Stunted bushes of a species of eucalyptus were 
the only trees seen, excepting the mangroves. The 
soil is composed of a mixture of red quartzose : 
