Correspondence map
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Stephen Lee
John Frederick William Herschel
John Frederick William Herschel invents the actinometer to measure the heating power of the Sun’s rays
1825
1826
John Frederick William Herschel publishes in the Philosophical Transactions
1826:
John Frederick William Herschel publishes “On the parallax of the fixed stars”.
1827
Joseph Nicéphore Niépce presents his photographs in England for the first time
1827
1828