Comments on the death of a mutual [?] acquaintance. Adds additional information about ancient constellations [see CP's 1841-10-29]. Complains about editors, publishers, and others who do not take CP's work seriously. [Many parts of this letter illegible.]

About some aspects of the magnetic survey, and who shall pay for it.

Recommends that William Whewell be appointed Master of Trinity College.

Expresses his great appreciation for informing JH of the honor being conferred by making JH a Knight Commander of the ancient and venerable order of Danneborg.

Asks HO if he can discover, without mentioning JH's name, what it might cost JH to be formally enrolled in Denmark for the honor he has received [see JH's 1841-6-20].

Thanks HO for his effort on JH's behalf [see JH's 1841-10-10], and then describes some of his photographic experiments.

Recommends awarding Royal Medal to [William Parsons] Lord Oxmantown for paper on large reflecting telescopes.

Reliability of measuring instruments used in scientific and public surveys. Approves George Peacock's suggestion to revise survey tables for use by non-scientist surveyors. Schools should teach only legalized systems of weights, measures, and money.

JH is captivated by science of photography. Has blundered onto 'Calotype leaving out [W. H. F.] Talbot's principal ingredient!!' [Note added by daughter Isabella Herschel:] Papa is in hurry. Greetings to family.

Replies to [?]'s questions about 'Mr. Bethune's suggestions' concerning terminology to be used for standards of weight and measure. Agrees with G. B. Airy that term 'land' should be used with 'land chain' unit.

Announces his invention of the 'calotype', and his application for a patent. Questions JH on his address to R.A.S., objecting to idea that universe is infinite.

Preparing his calotype paper for publication. Looking for a summer house, somewhere interesting to photograph.

Reports receipt of a communication, which argues that all elements are merely isomers of one substance. Expresses support for such a view.

Some details of improvements in the calotype method.

Sends JH sample of chemicals and paper to make calotype himself.

Has read WT's paper before the R.S.L. and now complains they will not print it in the R.S.P.T. as they understand it has appeared elsewhere.

Reports on paper by Samuel Brown to the Royal Society of Edinburgh on the conversion of carbon to silicon, and other transmutations. Reports on discovery of new element, ozone, and complains further about R.S.L. Council.

Expresses reservations about Samuel Brown's work. Apologizes for delay in trying calotype; has done only some vegetable substance trials.

Agrees to meet JH and Edward Sabine on Saturday. Kew Observatory was given to R.S.L., but R.S.L. has not yet taken possession of it. [JH annotation: election of General Morrison to R.S.L.]

Magnetic observatory is still not operational one year after FW's arrival. Thomas Maclear is now in 'Zwartsland' [Zwartkops?]. FW shares quarters with C. P. Smyth and William Mann. Hopes to begin observations next week at Cape Town and Simon's Bay; G. G. Lewis will make observations at Grahamstown. Problems with meteorological instruments. Proposes magnetic survey of entire colony. [JH annotation: Enquire what FW meant about measurement conversions, malfunctioning needle, and broken tube in 19 Feb. 1841 letter to Humphrey Lloyd.]