"If you feel astonished at my bringing man & brutes so near together in their whole nature (though with a wide hiatus) I feel still more astonished, as I believe, at your judgment on this head. I much wish you had enlarged your concluding sentence a little so as to say whether you consider the ordinary mental faculties so distinct, or whether you confine the enormous difference to spiritual powers including the moral sense.––"

Encloses copy of JH's letter to R.A.S. [see JH's 1864-6-29] that accompanied JH's submission of W. L. Newman's tables for determining radii of aplanatic lenses. Suspects that there was more than one volume of tables.