Up the Puruni River. 325 
once difficult and dangerous. One man indeed tried to 
cross on a tree leaning across the creek, but only suc- 
ceeded in becoming fixed, bundle on head, midway over 
the swollen stream and unable to move backwards or 
forwards without assistance. 
The placers or localities which have paid the 
best are those worked by the Messrs. Charles and 
Lawrence Forbes. The former is situated about 
three and a half hours' walk from the Puruni river- 
side, and has given nuggets weighing from a few penny- 
weights to several ounces. Much of the gold is coated 
with peroxide ot iron and some quite black with man- 
ganic oxide of iron , and is obtained from a depth of two 
to ten feet from the surface. Mr. Forbes' claim is 
quite close to the river and furnishes fine gold, mostly 
small grains and not large pieces. The site looks as though 
the river had originally flowed over the land, and the 
course of the stream subsequently changed to its present 
bed. 
The geological formation of the whole country, and the 
natural forces which have been at work there, are difficult 
to determine accurately. The country rock is gneiss, 
though quartz porphyry occurs at the Mara-Mara Creek, 
and granite in one or two places near the second and 
third falls. Through the gneiss the quartz ledges are 
interspersed, and here and there in the river, banks of 
quartz boulders may be seen when the river is low. Not 
far from the Essequebo Company's water-side camp a 
well defined quartz ledge 6 feet wide runs across the 
stream, but has not, I believe, been tested for gold. Be- 
yond the Mara-Mara, about half a day's journey, a curious, 
friable, dark brown, clay slate is met with, and here 
SS2 
