BEAUTIFUL SAND BEACHES 
which kept the boxes tightly closed, and they did not 
add to the comfort when one lay spread on them. 
When we left on the morning of July twenty-eighth, 
going along a beautiful stretch of close upon 25 kilometres 
in great expanses from 4,000 to 6,000 metres long, we 
passed first of all an elongated quadrangular island 1,500 
metres long; then, farther on, great masses of volcanic 
rock. At the end of that stretch the river divided into two 
channels separated by an equilateral-triangular island, the 
side of which was 2,000 metres, Minerva Island. Another 
island, also of great beauty, an 4 d with a considerable num¬ 
ber of rubber trees upon it, was found a little farther, 
and there a bar of sand spread beneath shallow water right 
across the stream. 
We had gone 31,500 metres that morning. When we 
found a most beautiful beach of lovely sand we could not 
resist the temptation of halting on it to prepare our lunch. 
Our surprise was great when we set foot on the beach to 
hear shrill whistles beneath us. The beach was formed of 
whistling, or singing, sand. The reason the sand was 
musical was because some large insects had bored thou¬ 
sands of holes of great depth into its moistened mass, 
which allowed the holes to retain their form. When the 
sand was trodden the pressure drove the warmish air con¬ 
tained in those holes with great force through the 
contracted apertures and caused a sharp whistling and 
occasionally quite melodious notes. 
I again took observations for latitude and longitude 
at this place, but I was beginning to find the work too 
heavy, not the observing in itself, but the computing of 
all the observations, at which I was not particularly quick. 
(Latitude 9° 24' south; longitude 58° 40' west.) Also, 
the great care which I had to take of the chronometer 
was a great trial to me, considering the numberless 
things I had to look after. The only little comfort I had 
on that journey had been my camp-bed, on which I could, 
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