Knows nothing of the enmity of Humphry Davy towards [John] Herapath. The purpose of JH's last letter was to point out that Herapath was in error in his solution of certain equations. Must consider correspondence closed.
JH's attempts with Edward Sabine to measure the difference in longitude between Greenwich and the Paris Observatory. Supplies, for Alexander von Humboldt, JH's measurement of Mount Etna's height. Gives message for François Arago concerning paper on magnetism published by JH and Charles Babbage.
Note to accompany the sending of a number of papers; comments on the orbits of double stars.
JH's mother will pay Mr. Beckwith to cover debt of MB's brother Thomas, who now owes Lady Herschel £1035. Comments on Thomas Baldwin's proposal for business partnership with JH and request for loan from JH.
Writing in response to claims made by Josef Fraunhofer, discusses the relative merits of reflecting versus refracting telescopes. Adds comments on double star observations made by JH and James South.
Asks JS to check over and forward to Astronomische Nachrichten JH's paper ['Letter on Fraunhofer's Claims for the Inferiority of Reflecting as Compared to Refracting Telescopes'], which paper calls attentions to errors in the catalogue of double stars published by JS and JH.
No summary available.
Thanks for the copy of his paper and errata. Received a packet of specimens of glass, which he presumes came from MF. Regarding the specific gravity of some of the specimens. Comments on further experiments to be made.
Gratitude to Gioenian Academy of Natural Sciences of Catania [Sicily] for electing JH a corresponding member. [P.S. 1 Oct. 1825:] Reports elevations on Mount Etna measured by JH with mountain barometer in July 1824, with confirmation by Niccolo Cacciatore. [JH's annotations explain sources of errors in elevations.]
'Messrs. [Apsley] Pellatt and Green' will fill the pots on Monday. JH will attend. Asks correspondent to attend also. Has sent for Michael Faraday's approval a formula for making [the glass].
Encloses note from Sir John Barrow refusing scientific instruments and objecting to using barometers. Supplying cameras and sextants to Admiralty's marine survey is not interference by Board of Longitude. Sent JH's expenses to Edward Sabine; has no further word on subject. Encloses Mr. Stewart's note about damages at Wrotham.
R.S.L. Council will meet 17 Nov. to discuss awarding its Copley medal; hence JS's paper, to be presented to R.S.L. later that day, cannot be considered for the award. Other matters have prevented JH from preparing annotations of JS's latest paper on double stars.
Thomas Young approved supplying [Richard] Copeland with two sextants and one mountain barometer.
Assures SW that slanderous reports regarding SW's nephew James White have not reached JH or Lady Herschel.
Has received copies of reprints from Lyell. Points out errors in a printed paper of his. Has been unwell and very busy of late. Would like to add DB's name to the Optical Glass Committee.
Edinburgh Institution's decision to order instruments from Josef Fraunhofer should send message to 'dilatory and ... abominably expensive' English artists. Axis of Fraunhofer's 8-foot transit instrument is too long. Compares those of Cambridge, Greenwich, Paris, and James South. [Robert] Woodhouse's paper in 1825 R.S.P.T. eliminated JH's hope that Cambridge would devote time to general catalogue.
Referring to the R.S.L. Royal Medals commissioned on 15 Dec. 1825 by King George IV, JH confirms that Sir Thomas Lawrence has agreed to design the medals.
Recovering from a prolonged illness. Discusses parallax. JH reports that he now is very skilled at sweeping with the 20-ft reflecting telescope.
Sending by the bearer mirror No. 3 of which he spoke. Will exchange it for Troughton's if TH can make use of JH's. Do not attempt to clean Edward Troughton's mirror with acid. Hopes he does not feel obliged to carry out any particular series of observations.