The key
was held down three times as long for the long flash as for the short one.
We found the best way of learning to send the signals properly was to
count 1 for each short flash, and for each pause between parts of the
letter, and 3 for each dash and for each pause between letters. Between
words we counted 6. Thus, for the letter A the key would be down when we
counted 1, up when we counted 2, down while we counted 3, 4, 5, and up
while we counted 6, 7, 8, for the pause after each letter. It was rather a
confusing code, I admit, but in time we mastered it, all but Reddy and
Fred, who never would learn, but instead used the wigwag code, letting a
short flash stand for 1, a long flash for 2 and a double long flash for 3.
The Double Mirror Instrument.
[Illustration: Fig. 161. The Double Mirror Instrument.]
Our heliographing instrument did excellent service sending flashes from
the cliff to the island, but we couldn't make it work very well sending
messages from the island to the cliff, because we had to face almost due
north, and then the sun was nearly always at our backs and couldn't shine
squarely on the mirror. This led to our building a double mirrored
heliograph the following summer.
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