Asks whether vegetable mould has an acid reaction. The contents of intestines of earthworms and castings are acid, which leads him to inquire about mould.

Discusses acidity of earthworm castings. JHG’s reply will make him more cautious.

Would like to see W. A. Detmer’s paper [Landwirtsch. Versuchs-Stat. 14 (1871): 248–300] and S. W. Johnson’s work [How crops feed].

Comments on food value of white and brown bread.

Returns the two books JHG had lent him. "I can plainly see I had better say nothing about the acidity of common mould."

Regrets that he has not strength enough to visit [Rothamsted].

Quantity of nitrogen in castings surprises CD.

Comments on papers: [J. B. Lawes and J. H. Gilbert, "Results of experiments on mixed herbage, pt 1", Philos. Trans. R. Soc. Lond. 171 (1880): 289–416; Gilbert, Lawes and M. T. Masters, "pt 2: The botanical results", Philos. Trans. R. Soc. Lond. 173 (1882): 1181–413].

Has never made sections to see how deep worms burrow – five or six feet is probable. Wishes the problem had arisen when he made his observations.