Thanks for and comments on paper on luminous and obscure radiation, particularly on extra spectral rays, incandescence of platinum, and experiment using transcalescence of iodine.

Is studying vesicles. JH's son [Alexander] may yet get Royal School of Mines appointment.

Asks JH to keep memoirs JT sent with regard to JT's application for position at University of Sydney.

Asks whether Michael Faraday's work with glass resulted in improved manufacturing or if rather its main scientific value was in discovery of diamagnetism.

Comments on excellence of the lecture at the Royal Institution of JH's son [Alexander].

Finds JT's work on thermotics 'highly interesting,' although criticizes measurements of 'tenuity' of vapor, and explanation of scattering of sunlight and formation of corona around moon during eclipse.

Gratified by JH's 'sympathy and approbation,' and that JH's writing and spirit remain 'firm' and 'fresh.'

Asks permission to print extract of JH's letter on heat spots of spectrum of rock salt sample. Hopes JH's son [Alexander] will speak at Royal Institution; JT would help with illustration. Wonders how blue color of water relates to sky color and polarization.

Thanks for work on diamagnetism and magne-crystallic action [Researches on Diamagnetism (1870)], which JH is excited to read. Mentions long-abandoned plans for magnetization experiments. Envies those who can see JT's 'magic' experiments at Royal Institution.

Remarks on physical properties of ice and their bearing on glacial phenomena. Asks for help inventing term for idea of 'fracture and renewal' of glacial bendings.

Asks JH to be a shareholder in venture to publish new weekly scientific journal.

Thanks for papers on diamagnetism and lecture on 'slaty cleavage.' Compares with phenomenon of 'ringing coins' in mint. Explains with examples conformity of JT's views with JH's own on geological stratification. Praises simplicity yet completeness of JT's work.

Encloses reference to one of JH's letters to JT that has already been printed.

Wishes luck but expresses inability to help with new science journal [see JT's 1864-11-18].

Thanks for JH's suggestions on JT's outline of comet speculations. [G. B.] Airy, too, has replied. Includes more speculations on 'envelopes' and nucleus of comet.

Likes JT's explanation of sky's blue color. Has difficulty with JT's explanation of polarization of skylight. Comments on absorptive powers of vapor and liquid.

Describes experiment involving viewing spectrum of a light flash as it advances and recedes. [Marked 'not sent on further consideration.']

Reply to JT's 'Remarks on Radiation and Absorption.' Calls non-absorption of air and vapor key to understanding meteorological phenomena. Remarks on 'radiant heat' from moon.

Thanks for and comments on paper and lectures on 'diathermancy &c' of gases, scientific teaching, and solar chemistry. Regrets that JT mentioned all names connected with light research except JH's. Remarks on absorption of light, molecular vibrations.

Remarks on JT's papers on radiant heat and related role of moisture. Will send requested sample of rock salt. Explains difficulties using it and hopes JT will have better success, perhaps even repeating JH's experiments.