Has been observing sunspots and talks about sunspot cycles; JH is glad to see that son John has been practicing observing with the spectroscope in preparation for the Indian solar eclipse [see JH's 1867-6-12].
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Has been observing sunspots and talks about sunspot cycles; JH is glad to see that son John has been practicing observing with the spectroscope in preparation for the Indian solar eclipse [see JH's 1867-6-12].
Provides sources of information about polarization, spectroscopy and solar physics for son John, who is continuing his preparation for observing the solar eclipse [see JH's 1867-9-12].
Has heard from Emma, son William's wife, that the solar eclipse will occur in the rainy season, and thus will not likely be visible [see JH's 1867-9-29]; JH is wondering if the equipment from the R.S.L. arrived safely.
Speaks of the awkwardness of some telescopic instruments, but urges son John to persevere; comments favorably on daughter Amelia's prospective husband, Thomas Wade, and comments disparagingly about the government's introduction of a metrication bill.
Comments on son John's spectroscopic and telescopic observations, and encourages observing a particular nebula, as it has been reported as having changed shape since JH observed it in the 1830's.
Is anxiously awaiting details of son John's observations of the solar eclipse in India; JH sends details of sunspots observed by JH on 18 Aug., and concludes with family news.
Congratulations on success in observing solar spectrum and corona. JH's views on sun's corona [with diagram]. Agrees that communications in India are abominable.
Reports his observations of the nebula around Eta Argus. Provides a sketch. Has observed fifty other nebulae.
Provides further [see JH's son's 1868-11-23] observations, along with drawings, of the nebula around Eta Argus.
Talks about problems of observing nebulae—one of which seems to have changed—and one of which is in the catalogue and does not seem to exist.
Forwarded both of John's papers on solar observations to William Huggins. Comments on solar prominences and spots, and on Eta Argus. Concern for Esther's fever. Report of 'great meteor' seen at Collingwood. Alexander Herschel came home from Glasgow with new device called 'bicycle' that amuses neighbors. Explains optics problem in telescopes. English system of measures.
Glad for Mary's recovery. Congratulations on John's promotion to captain. Suggests method to study solar prominences without spectroscope. [Letter continues 15 June:] Alexander Herschel reports that G. B. Airy tried this method unsuccessfully long ago, but JH is sure it will work.
Asks son John to stop at the British Museum and get the completion of a quotation JH needs; also asks John to pick up JH's R.S.P.T. copies not picked up recently.
Is not prepared to come to any distinct conclusions about the effect of local attractions in geodetic surveying, but talks about the problem for the whole letter.