Describes observations made as he travelled and people visited on journey from London to Ancona.

Talks about Josef Fraunhofer's failing health and his making of flint glass.

Is sending on two items directed to JH through WT.

Questions and comments regarding improvements in microscopy.

Comments on several experiments with spectra passing through glass films.

Will send JH some barometric observations; describes the barometers with which the observations were made.

Discusses casting and construction of telescope speculae.

Discusses construction of his 20-foot reflecting telescope, which he modeled after the 40-foot reflector at Slough. Discusses differences of gallery and asks for advice.

Heard election for position in London will not take place for several weeks. If JH can secure situation in Virginia for WR, WR will accept it.

Accepts dinner invitation. Hopes no emergencies arise that would prevent their visit.

If possible, send a magnetic needle and the prescription for mixing chrome green paint for Mrs. Somerville. Enjoyed visiting JH's mother.

Encloses a copy of a letter from the astronomer [George] Fisher, who strongly supports the practicability of work in Spitzbergen. Says the letter will be presented to the Council for its consideration in hopes that a special committee will be appointed. Urges JH to show the members the copy.

Claims 'it never entered [his] head' that an appointed committee would be influenced solely by the need to defend its decisions. Restates his opinion that the subject should be properly considered.

Thanks JH and Charles Babbage for their paper on the magnetic experiments. Asks to have 20 extra copies of the paper on the rocket experiments made when it is printed. Speaks of travel expenses. Mentions [T. F.] Colby's opinions regarding the Spitzbergen measurements.

Announces a new step to all astronomers toward understanding the solar system due to work of [Thomas] Clausen of the Altona observatory. Clausen recognized that the comet discovered by Biela was the same as that of 1805 and 1772. HS gives details of circumstances.

Offers to participate in determining stellar parallaxes by finding the angle position of double stars. Apprises Henry Kater that he has never seen Saturn's rings separated. Includes micrometer measurements of Saturn and Jupiter.

Mentions a four month absence from Dorpat. Commends [James] South on his work on double stars yet states that South's distances for nearby stars are too large. Considers his measurements, previous to his [Josef] Fraunhofer telescope, significant, even if South refuses to accept them. Thanks JH for the difference in the longitudinal measurements between Paris and Greenwich.

Interested in JH's catalogue of dimmer double stars. Worries about determining parallax of very close stars. Points out mistake in JH's formula for determining 'the maxima and minima of the position angles.' Informs JH of German translation of William Herschel's writings, Wilhelm Herschels sämmtliche Schriften.

Thanks JH for material from AS of London. Mentions 'new comet.' Informs JH of being nominated to the list of foreign members in the American Philosophical Society.

As MF will be unable to attend the next meeting of the Glass Committee, he sends JH the analysis of the glass produced in one experiment, emphasizing its consistency and high quality.