87 
catchment. Near the back of the dam one of the diorite dykes 
very common in this district crosses the Cordingup Creek, and at 
this point it was found that there was an exudation of salt water in 
small quantities, but sufficient gradually to affect the fresh water, 
and to require special measures to be taken to cut off the salt water 
feeder. It is incredible that this salt should be leached out of 
either the solid crystalline granite or the equally dense crystalline 
diorite, both of which are practically unweathered at this point, but 
there is nothing strange in there being salt water in the fissures 
along the margins of the <lyke. ExceiK for a short time during 
rains almost all the natural waters of the Ravensthorpc district are 
very salt, whether the bedrock is granite or diorite, and salt water 
must therefore be expected to accumulate in all joints, breaks, and 
other fissures of the rock. 
By tracing the conditions of salinity of the country from the 
south coast northwards, the writer thinks that we shall be able to 
see an explanation of most of the phenomena exhibited, and to 
conclude that they are in keeping with the theory of marine 
submergence, though mexi)licable on that of sub-aerial pcneplana^ 
tion. All along the south coast from Albany eastward to Esper- 
ance, the country is very salt, most of the streams — even running 
ones— being quite undrinkalfie even l>y cattle during the drier parts 
of the year. When Hooded by rains they may he fairly fresh for 
a little while, but they soon become salt again, and even in rains 
the spectacle may ])e witnessed of a rushing turbid torrent of salt 
water. The Palinup Rirer, Salt River, Jacup River. Hamersley 
River, and Phillips River may generally be seen running a little, 
where crossed in travelling from Albany to Ravensthorpc. but 
are very salt. On the granite rocks near the head of the Hamers- 
ley River, there is a camping place where a little fresh water may 
generally be obtained. Init where the writer found that nearly all 
the water trickling over hare granite was quite salt. Vet it is not 
the granite which is yielding the salt, for rock holes in the granite 
are found in which the water remains perfectly fresh for weeks. 
The celebrated Night WT'll on the Salt River was in granite in 
the valley of the river and only a few feet above its bed, and above 
it and below it in the bed of the river there were salt water ])ools 
when the writer visited it in 1902. 'I'he fresh water was in a 
crevice in the granite and so had every op])ortnnily to dissolve salt 
from it if the granite were the source of the salt, but the water 
was quite fresh. So also tanks blasted out of the granite, and 
with a bare granite catchment, in other parts of the southern dis- 
trict. retain their water perfectly fresh. The hard granite evi- 
dently is not the source of the salt, hut all the overlying soil and 
the sand plains appear to be full of salt. It is clear that every time 
the streams run they must carry away a large amount of salt to 
the sea, and it is an indication of the enormous amount of salt 
available, and also of the comparatively short time during which 
