92 Lectures on the Geology , Botany, fyc., of the 
sandstone, which has been broken through by basalt, near the 
divisions of the waters of the Gulf of Carpentaria and the north¬ 
west coast. 
8. The eighth part of my journey comprises the two Alli¬ 
gator Rivers, and the Coburg Peninsula. Its leading features are 
large swampy lagoons; extensive plains at the lower part of their 
course, densely wooded ironstone ridges, and a great number of 
creeks in the Coburg Peninsula, with limited flats of light alluvial 
soil, which are richly clothed with herbs and grasses during and 
immediately after the rainy season. These creeks generally en¬ 
large into swamps called “ Marairs” by the natives, before they 
arc lost in the mangrove thicket, which covers their junction with 
the sea. 
I have mentioned that at the east coast we enjoyed a regular 
cool northerly night breeze, which frequently increased to a gale, 
and that round the gulf the strong night breeze was southerly, 
from south-west and south-east, whilst the sea-breeze blew during 
the afternoon from the northward. We were deeply interested in 
these movements of the atmosphere, not only on account of their 
meteorological importance, but also on account of the relief which 
they afforded us whilst under the influence of a scorching tropical 
sun. 
Along the Roper the sea-breeze continued strong and regular 
from the eastward, but the night-breeze became indistinct, probably 
in consequence of a great number of parallel ranges, which inter¬ 
cepted its course. At the head of the river, however, we again 
felt a strong but warm wind from north-north-west—north-north¬ 
east, about nine o’clock at night. This I considered to be the 
sea-breeze from the north coast of Australia, flowing probably up 
to the high land along the valley of the Liverpool River. 
The 14th November, when on the high land of Arnheim’s Land, 
and on western waters, we experienced the first thunder-storm 
since we had left the east coast. Similar ones rose almost every 
day to the 23rd of November, and veered invariably from south to 
west, from north to east. It was the time when the north-west 
monsoon sets in, and these thunder-storms appeared to be the 
first indications of the change. 
