About an increase in sun spot activity.
About an increase in sun spot activity.
Glad that Emma's jaundice is over. Criticises metric system of measure. Encloses JH's response to Mr. Yates's letter in the Times on Geometrical British System. Upset by present resistance to anything English. This is what 'lost us...Neptune.' Would like to see Arabic translation of Outlines Astr. Relieved that 'shabby' French translation by [L. M. J.] Chevigné was stopped. Failure of gold standard in India. French and English coins. Suggestions on WJH's effort to introduce oaths into Indian justice system. Popularity of velocipedes [bicycles]. Family news.
Has read the syllabus of GA's lectures on magnetism; it reminds JH of his attempt to solve the problem of 'Mahomet's coffin', which JH still believes would work.
Is considering a new edition of Outlines Astr.[?] and wants to provide the latest determinations of the periods of rotation of the planets.
'Great Comet of 1843' presents difficulties for JT's explanation of comets' tails [continuation of JH's 1869-5-28].
Thanks HR for sending HR's book on spectrum analysis [Spectrum Analysis, 1869]. Praises that publication.
Suggests experiments with regard to polarization and vaporization, and comets' tails.
Thanks for paper on comets. Offers questions, problems to be resolved, particularly on termination of comet.
Thanks for the gift of the paper on color. Comments on this and the subject in general.
Comments on 'rubbish' published by Poet Laureate, EC's report of the weather of 1849, and the flowers and plants growing in JH's garden.
On AD's and JH's illnesses; asks AD about Latin verses of the medieval period.