On the observation of sun spots.
Showing 1–15 of 15 items
On the observation of sun spots.
Received report by Lord Monteagle [Thomas Spring-Rice] on Standard Platinum Pound. Agrees to participate with members of 1853 Standards Committee in reexamining standards.
Encloses copy of JH's essay entitled The Yard, the Pendulum, & the Metre... (1863). Speculates on causes for deviation in pendulum measurements. Recommends using torsion gravimeters in 'proposed operation.'
If enclosed item is accepted for publication in Photographic News, JH wants to inspect its press, especially 'as respects the Cipher,' and to receive 25 copies.
Note accompanying report on paper by G. B. Airy.
Responds to GS's 1864-1-16.
FM has published, in translation, JH's article ['Weather and Weather Prophets' (1864)], already published in Good Words. JH was not aware that this was FM's intent, and JH warns him that some editors may be sensitive about such matters.
Reports on G. B. Airy's analysis [R.S.P.T., 153,. 617-] of 177 magnetic storms.
Raises with GA the likelihood of an error in a date of a transit of Mercury in a paper by F. A. Winnecke.
Thanks for FA's star atlas series, one of which is a duplicate; reports apparent variation of a nebula.
Mistaken about seeming duplicate [see JH's 1864-1-28].
Has been asked to reweigh the damaged Parliamentary standard pound weight; thinks that W. H. Miller would be a more suitable person to do the job.
Asks that consideration be given to 'wishes of the Cadet' in selecting a regiment for him.
In response to the gift of a book, JH comments on the philosophy of knowledge, and goes on to say that JH agrees with [John Stuart ?] Mill's rejection of the syllogism as a means of argument. In the postscript, JH comments on the nature of heat.
About geodesic books and JH's encouragement to John to keep asking questions; indeed JH is almost insistent on son John's writing to JH with questions, book needs, and confidences. JH also talks about finding the arithmetical mean of a number of observations. [Also included is the 1st page of a letter to John from one of his sisters.]