Correspondence map
Interact with the map by zooming, clicking hotspots, and selecting items to see more details. Hit play on the timeline to show correspondence over time.
Charles Rigobert Marie Bonne
John Frederick William Herschel
John Frederick William Herschel invents the actinometer to measure the heating power of the Sun’s rays
1825
Autograph letter signed by sender. Edward Sabine's and John Frederick William Herschel's memoir on the differences of the meridian between Greenwich and Paris. Hopes to print a notice of the same operation with similar results. Operations last year between Paris and Brest were not a success so hopes to repeat them this year.
6 March 1825 Sender: Charles Rigobert Marie Bonne Reference number: HS/4/183
Autograph letter signed by sender. Concerning recent works and discussions connected with longitude.
11 June 1825 Sender: Charles Rigobert Marie Bonne Reference number: HS/4/184
Autograph letter signed by sender. Has returned to Brest, and found his letter. Is honored to correspond with John Frederick William Herschel. Further regarding pendulum observations.
28 June 1825 Sender: Charles Rigobert Marie Bonne Reference number: HS/4/185
Autograph letter signed by sender. Is sending him a paper dealing with the measurement of the arc of the meridian between Greenwich and Paris. Further observations along the coast by Lieut. C. L. Largeteau.
1 July 1825 Sender: Charles Rigobert Marie Bonne Reference number: HS/4/186
Autograph letter signed by sender. Has just received his letter of 27 June. Further work of Lieut. C. L. Largeteau. Longitude readings at various points.
1 July 1825 Sender: Charles Rigobert Marie Bonne Reference number: HS/4/187