Letter from Edward Sabine, London, to Col WH Sykes On communications from Lieutenant Yule, Bengal Engineers, Aden, describing the poor condition of the instruments with which Yule was expected to use in the construction of an observatory in Aden for magnetic observations. Sabine states that the description of the instruments by Yule should not have prevented the observatory from being built. He further states that if Aden is to be kept as a magnetic station, a new officer, freshly trained in observational techniques, will have to be sent there. 20 November 1840