Letter from J [John] Herschel, Brompton Barracks, Chatham, to 'Dear Mama' [Margaret Brodie Herschel] He forwards letters which he hopes not to have kept too long and his father's paper. He discusses architectural notes, including on making 'a common brick house. Ugh!', but considers that there is some value in them. He asks if Margaret has read about their exploits before the Duke of Cambridge [Prince George, Commander-in-Chief]. Herschel describes the Duke as a good-looking man but wishes he would not keep them in a hot sun doing nothing. He explains the recent manoeuvres with the aid of a sketch showing the ordering of regiments, with the Royal Engineers to the right, 'being the more honourable corps', and the delays caused by the long line formations. Once in line 'not a man may move' even when standing at ease. They were in line for two hours while the Duke rode up and down the line. Once inspected there was a march past by batallion, again with a sketch of quarter distance column. He explains the distance between each two divisions and sketches the wheel-past the Duke. They all passed in half an hour and then closed up before marching past the Duke again in close order. He notes a 'derivation' for his father citing Brande's Chemistry. n.d. [May-June 1857?]