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with ring photometer rendered translucent with spirits of turpentine oil
Toward candle    799
Towards lamp    13.65
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              2)21 64
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average         10.82
By equality of illumination 
mean of 10 sets 9.51
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with tracing paper
Toward candle   5.15
Towards Lamp   23.90
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             2)29 05
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mean of ---    14 50
2 exp each way
[[strikethrough]] This [[/strikethrough]]
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[[in pencil]] 37
with equal illumination two sets mean 10.00

From these results is apparent that the mean with this or more translucent paper is not the safest since the extremes are so far apart.