Letter from Horace T [Tabberer] Brown, 52 Nevern Square, Kensington, to [Joseph] Larmor 'It is the willing horse which is ridden the hardest'. He asks Larmor to look at a section of text he has re-written. The application of Larmor's last formula has brought out more new points in the experiment. He asks if the formula for the septum placed in the middle of the tube is applicable to other cases. He will apply the new results to diffusion through the pits in the cell walls. 22 May 1900