Asks JH about a comet JH had been observing. Notes the publication of J. S. Mill's System of Logic, describing it as closer to JH's than to WW's position.

Concerning the great comet of 1843, JH remarks that both Thomas Henderson and Johann Encke noted that the comet bounced off the sun's atmosphere.

There is to be another cliff-blasting. Gives details of travel arrangements.

Has received the two memoires on photographic processes and rays of the solar spectrum. Presumes JH has now received his own work on Physical researches. Comments on various electrical experiments.

Thanks TA for papers on heat of acid-base reactions.

Regarding the recent comet, believes it to be the one of 1668. Does not feel competent to comment on the proposal to change the names and boundaries of the constellations.

Offers JH information about, and maps of, Switzerland, as GA understands JH is going there.

Sends some specimens of photographs he has made by using bichromate of potash and an acid solution of nitrate of mercury. Gives details of a luminous phenomena he has seen in the S.W. and would like an explanation of it from JH.

Refers JH to page 18 of memoir of Manchester Literary and Philosophical Society, in which JJ, using 'the magnetic electrical machine,' succeeded in proving 'that heat may be generated by mechanical power without accompanying chemical change.'

Gives his proposal for the amendment of nomenclature for the northern constellations. F. W. A. Argelander's new celestial atlas. Regarding JH's southern map. The letter from the B.A.A.S. has been sent to Sir Robert Peel.

Introducing Professor Emile Plantamour, who is visiting England. Read JH's article on the rays of the solar spectrum with pleasure. Sends some articles by Plantamour from recent journals.

Met JH when he was residing in the Auvergnes. Since then he has had to leave France and now resides in England, where he is making a living teaching French and writing books. Would be grateful if he could add JH's name as a subscriber to a forthcoming work.

Thanks WH for his drawing of the comet, which JH will communicate to the R.A.S.

Unable to write before as he was packing for his journey home. Regrets none of his northern friends had seen the comet. Its orbit has been calculated as 35.3 years. Remarks on the tail of the comet.

Acknowledges with pleasure JH's kind note. Owes much to JH's book in the chapter on experimental methods. JH will doubtless find Auguste Comte's book worth reading. Would like a note of any errors in JM's book.

Urges JH to study a temporary index made by William Herschel that contains observations about types of zodiacal light.

Wishes JH had added his name at the head of the list of subscribers. Thinks he is being too cautious. AJ is responsible for the whole of the work though it appears under two authors.

Has been able to obtain some deodar seeds from Ireland. Sends them, together with some seeds of the Himalayan cypress. Hopes they will prove a success.

No summary available.

Describes a particularly brilliant aurora, which JH observed from Collingwood on the night of 6 May.