Slough - Baker, [Richard] Gwatkin and Wilkinson have been staying with Herschel. He is pleased Whewell is undertaking something definite but wishes it was 'something entirely original. Still I hope your transl. of the application of Geom.y to Alg. will be useful'. Whewell should give all the forms relative to ellipses of small and large excentricity. A 'compendium of them is a great desiderium'. There 'are divers forms respecting the intersection of strait lines in space which are of the most eminent use in optics which would be valuable'. Herschel has been working at the demonstration of Stewart's theorems. Hershel's work on algebra 'goes on steadily but not very rapidly'. Judging by Whewell's query it does not look as if he is doing much about functions.