Work will begin on obelisk at Feldhausen. Occultation of Gamma1 and Gamma2 Virginis observed. Triangulation survey will take TM away from Royal Observatory for extended time. Slave ship carries small pox and causes outbreak. Parallax observations show brightest stars, not nearest.

Will send information from observatories where aurora are visible. Discusses occurrences at various observatories and a letter from [C.] Kreil to [A. T.] Kupffer regarding his observations.

Devotes his spare time to optics and has made several telescopes. Would welcome his advice on where to obtain good quality flint glass.

Writing on behalf of John Russell, asks that JH inform T. J. Paterson of his appointment to a position teaching in the Government Schools at the Cape of Good Hope. Mentions travel arrangements for those appointed.

Promises to help JH obtain materials for experiments including mercury and silver ore.

Has been applying his mode of calculation for the barometrical heights for the years 1815-23 and sent the results to the R.S.L. As JH may not see them he sends a few comments on them. Would like a suitable colleague to share his labors.

Writing on behalf of John Russell, asks that JH inform Francis Tudhope of his appointment to a position teaching in the Government Schools at the Cape of Good Hope.

Discusses what instruments should be given to Palon Boguslawski. Discusses tidal observations, noting the complexity of the results obtained.

Loading scientific instruments aboard ship [Anshimy?] tomorrow prevents JB from visiting JH before departure. Missed annual R.A.S. meeting. Book of 'Observations' is nearly finished. Told [J. C.] Melvill that instruments in India were not adequate for observations of astronomical refractions.

Both William Whewell and George Peacock agree to using the magnetometers, forms, books, etc, but do not agree to the provision of actinometers [for the equipping of terrestrial magnetism stations??].

Alerts RS to the fact that there is an 'underhand sale' of the prints of [H. W.] Pickersgill's portrait of JH going on, as JH's cousin bought one.

Waited until after 14 Feb. to submit JH's paper on photography ['On the Chemical Action of the Rays of the Solar Spectrum...,' R.S.P.T. (1840), 1-59]. Will send WT a copy.

Assures JH that engravers typically take for themselves a few copies of any print they have made. If a large number of these appear for sale, then it is fraud. Suggests JH not act because the engraver is 'insane' and the exposure would hurt his family.

Thanks JH for suggesting that the R.A.S. write to King Christian VIII, but requests that JH include his own name and mention Astronomische Nachrichten.

Hears that JH is to be one of his parishioners. Outlines the local educational establishments. Should be grateful to know if JH would be subscribing towards their upkeep.

Concerned about the Daguerreotype patent in England, and questions at some length a paper on the origin of freemasonry.

More on machine-made curves [see HP's 1840-1-28].

Needs the name of the print seller from whom JH's cousin bought the copy of the print of JH's portrait, so RS can learn how many copies are available. RS will then know whether to 'treat with [the printer] as an honest man or a rogue.'

JH concerned not so much that a few copies of the print of JH's portrait may have been sold, but that the plate itself may have been stolen and sold. Seems relieved to know that the plate was left with the printer, not the engraver. Asks RS to make an inquiry with the printer.

Outlines theory behind and method for preparing thermographic paper, which allows observers to determine 'what share each ray of the spectrum bears in producing the observed total effects.'