Definition at the Observatory last night was abominable; therefore no comparisons can be made between the stations. Much obliged for the details of the actinometer. Will call on JH later.
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Definition at the Observatory last night was abominable; therefore no comparisons can be made between the stations. Much obliged for the details of the actinometer. Will call on JH later.
Thinks Monday 2 Jan. a suitable day for taking down the Circle. Has engaged J. K. Gibbs the carpenter for the coming quarter. No official notice has been taken of his Colonial Measure of Reference.
From a newspaper received today sees that John Pond is dead and buried. Affair of James South and Edward Troughton and William Simms is as before. Sends the observations of the 21st; rain was not good for astronomical observations. Comments on these readings.
Setting a unit of measurement for solar radiation (the 'actine'); proposes to 'take for a unit of solar heat that which if all employed in heating a cubic inch of water exposing a horizontal surface of one square inch, to a vertical Sun during one minute would produce a dilation of one thousandth part of its volume.'
Testing whether an actinometer with a glass back is more accurate than one without.