Practised at Earls Colne, Essex, until his death in 1868. In 1818 he presented "The Original Obstetric Instruments of the Chamber-lens" to the Medico-Chirurgical Society. (See "Brief notice presented to the Medico-Chirurgical Society with the original obstetric instruments of the Chamber-lens," by H H Carwardine, *Med.-Clair. Trans.*, 1818, ix, 1856.) A collection of relics, including letters of Dr Peter Chamberlen, had been found in a chest which had lain for many years in a closet at Woodham Mortimer Hall, near Maldon, Essex. The estate and house had been purchased by Dr Peter Chamberlen previous to 1683, and had continued in his family until 1715. The obstetric instruments had been given by the finder to Carwardine. They consisted of adaptations, in a pair of the simple vectis, with an open fenestra. Chamberlen had the idea of uniting the two by a joint. He had tried a pivot and socket at the fulcrum, but in an improved and lighter instrument he had simply made a hole in each fulcrum, through which, after each vectis had been put into position against the head, the two blades could be sufficiently approximated to be held together by a tape passed through the holes. The next step was made by Smellie, who invented the 'English-lock'. The whole subject was discussed by Robert Lee in "Observation on the Discovery of the Original Obstetric Instruments of the Chamberlens" (*Med.-Chir. Trans.*, 1862, xlv, 1). Carwardine conceived the idea of writing Memorials of the craft of surgery, and composed a chapter or two, but gave up the undertaking as he was unable to gain access to the Records of the Barber-Surgeons. This task was carried through by John Flint South, and the results were published in 1886 with the title, *The Craft of Surgery*, under the editorship of D'Arcy Power, FRCS. There is an autographed photograph of H H Carwardine in one of the College Albums.