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The Sir John Herschel Collection
The preparation of the print Calendar of the Correspondence of Sir John Herschel (Michael J. Crowe ed., David R. Dyck and James J. Kevin assoc. eds, Cambridge, England: Cambridge Univ. Press, 1998, viii + 828 pp) which was funded by the National Science Foundation, took ten years. It was accomplished by a team of seventeen professors, visiting scholars, graduate students, advanced undergraduates, and staff working at the University of Notre Dame.
The first online version of Calendar was created in 2009 by Dr Marvin Bolt and Steven Lucy, working at the Webster Institute of the Adler Planetarium, and it is that data that has now been reformatted for incorporation into Ɛpsilon.
Further information about Herschel, his correspondence, and the editorial method is available online here: http://historydb.adlerplanetarium.org/herschel/?p=intro
No texts of Herschel’s letters are currently available through Ɛpsilon.
Describes JH's location at the Cape and his observational sweeps, lists nebulae and double stars, as well as comet and eclipse observations. [Letter finished on 1835-3-5.]
Comments on CW's work on light and on the velocity of electricity. JH's ruminations lead him to the idea of motion pictures.
Comments on the possible loss of some mail going to England, the longitude of Mauritius, and the tides at the Cape. Wonders if anyone was able to observe Halley's Comet during the recent solar eclipse.
Reports on location of a planetary nebula. Expresses thanks for book by [Robert] Woodhouse.
Has interpolated the hourly tidal observations for Simon's Bay.
Reports having read the record JH sent of [tidal] observations and comments on it.
Suggests a means of resolving TM's problem with the mural circle.
Found Encke's Comet the night before last. Has not had a chance to see Halley's Comet. Will JH come to the Observatory? There are no fleas.
Is glad JH has given his opinion to Francis Beaufort on the subject of observations of the first class. Encke's comet is invisible in the 14-ft. within the range of 10 degrees. Last two nights were very favorable. Has seen Encke's comet three times, and it appears just as he saw it in England.
Describing JH's observations and comparing notes.
Responds to TM's query in his 1835-1-17 about the effect that motion of the center of the mural circle would have on the microscopic readings.
Additional approaches to resolving TM's mural circle problem [see JH's 1835-2-5].
More on the mural circle [see JH's 1835-2-7].
Some comments about constant error in TM's observations.
About the difficulty of measuring high and low tide with the instruments available to TM; offers the design of an instrument that would measure the mid-point between high and low tides.
Excited about JH's observations, and has shown them to several people.
Sends TM some tide observations, and some calculations done on them.
Believes that TM is the first to see the return of Halley's Comet [see TM's 1835-9-1].
Still struggling with the problems inherent in using the mural circle; the comet has apparently been seen by JH's mechanic, John Stone, prior to having been sighted by TM.
Sends information about where to look for Encke's comet.