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Contributed by American Museum of Natural History Library.
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Transcription
Refraction Tables,
Temperatures.
Cenligiral.
To reduce Fahrenheit &
centigrade degrees, add 32
and multiply by 5/9.
Example.
20 below zero Fahenheit =
20+72 = 52 x 5/9 = 260/9 = -28
altitude of Sun -30°C -25°C -20°C
8° 7.49 7.33 7.16
90 6.69 6.55 6.42
100 6.04 5.91 5.80
110 5.50 5.37 5.27
120 5.05 4.94 4.85
130 4.66 4.56 4.47