160 IOWA STUDIES IN NATURAL HISTORY 
Vitilevu, henee I will confine my remarks to some notes of a 
geological nature. First of all, however, I wish to acknowledge 
my indebtedness to Colonial Secretary Fell who accompanied us 
on the trip. By careful planning and excellent organization every 
detail was so well thought out beforehand that the trip was a 
pleasure jaunt rather than one of almost insurmountable difficul- 
ties; guides, porters, polers for the boats, cooks, interpreter, and 
even a private secretary made up a large retinue. A royal party 
eould not have been more welcome than we as we were met with 
ceremony, feasted, and entertained in one Fijian village after an- 
other. Mr. Fell managed the whole journey without a hitch; he 
was very popular with the natives, highly respected by the bulis 
or chiefs and a jolly good fellow at all times. He has our ever- 
lasting gratitude and good will. 
The Navua river drains a fairly large territory. Its lower 
reaches are wide and affected by the tides for some distance and 
the land on either side is a very fertile delta plain. As the land- 
ward edge of the plain is reached, the valley narrows perceptibly, 
the gradient of the stream increases, and rapids are frequent. In 
places the valley walls are steep and rocky, almost perpendicular 
at times. There is little or no valley flat except a few square rods 
at the turns. Over the steep, tree-fern covered slopes small tribu- 
taries come tumbling in, some as silver threads of water, others 
with great turbulence. At a point some sixty or eighty feet above 
tide, as accurately as we could estimate by the aneroid, the gorge 
is quite narrow with sides and floor of solid rock. There is no 
doubt but that a well constructed dam here would impound con- 
siderable water and that a hydro-electric plant capable of generat- 
ing much power could be built. Our visit was made during the 
dry season and yet the volume of the stream was sufficient for 
a considerable amount of power. High water marks on the sides 
of the valley gave indication that during floods immense volumes 
pour down the gorge with great violence. This fact, of course, 
is the one to be most carefully considered in planning a dam. 
But by making it extra heavy and of good material there should 
be no difficulty. Records covering stream discharge and flood 
measurements are doubtless available. If not it would be a wise 
policy to aequire such data on each stream which is a potential 
source of hydro-electric energy—and there doubtless are several 
in a region where the annual rainfall is so great. The rock at this 
