oe and at an angle of forty-five degrees. Each pair of slabs
was perforated by a longitudinal slit and they were joined firmly at
their extremities by finely carved and richly painted end-pieces.

The operator strikes the slabs with a wooden mallet or hammer, the
head of which is wrapped with an inch layer of caoutchouc and then
with a cover of thick tapir-skin. Each section of the wooden slabs
gives forth a different note when struck, a penetrating, xylophonic,
tone but devoid of the disagreeably metallic, disharmonic bysounds of
that instrument. The slabs of wood were suspended by means of thin
fibre-cords from the crosspieces, and in this manner all absorption
by the adjacent material was done away with.

By means of many different combinations of the four notes obtained
which, as far as I could ascertain, were _Do--Re--Mi--Fa_, the
operator was able to send any message to a person who understood
this code. The operator seized one mallet with each hand and gave
the thickest section, the _Do_ slat, a blow, followed by a blow with
the left hand mallet on the _Re_ slat; a blow on the _Mi_ slat and on
the _Fa_ slat followed in quick succession. These four notes, given
rapidly and repeated several times, represented the tuning up of the
"wireless," calculated to catch the attention of the operator at the
_maloca_ up-creek. The sound was very powerful, but rather pleasant,
and made the still forest resound with a musical echo. He repeated this
tuning process several times, but received no answer and we proceeded
for a mile. Then we stopped and signalled again. Very faintly came
a reply from some invisible source. I learned afterwards that at
this time we were at least five miles from the answering station. As
soon as communication was thus established the first message was sent
through the air, and it was a moment of extreme suspense for me when
the powerful notes vibrated through the depth of the forest. I shall
never forget this message, not only because it was ethnographically
interesting, but because so much of my happiness depended upon
a favourable reply. I made the operator repeat it for my benefit
when we later returned to our village, and I learned it by heart by
whistling it. When printed it looks like this:

After each message the operator explained its meaning. The purport
of this first message was so important to me that I awaited the
translation with much the same feelings that a prisoner listens for
the v