ST. AGNES contains upwards of 300 inhabitants, and is situated about a mile to the south-west of St. Mary’s. It is extremely pleasant, fertile, and well cultivated, but is chiefly remarkable for its beautiful light-house. This highly useful structure was completed about the year 1680, under the superintendance of Mr. Adam Walker, the celebrated lecturer on natural and experimental philosophy; it is upwards of 60 feet high, and is built on a very elevated spot. The light is produced by several parabolic reflectors of copper, plated with silver, and each having an Argand’s lamp in its focus, supplied with oil from behind. The frame in which the reflectors are disposed, stands perpendicularly to the horizon, on a shaft united to a machine below, that turns the whole round every two minutes; by this motion the light progressively sweeps the whole horizon, and by its gradual intermission and increase, is readily distinguished from any other; its brilliancy is also extraordinary; and by these combined effects, its benefits are greatly increased, as the seaman is at once rendered completely sensible of his situation.[54] The charges attending the erection of this light-house, were defrayed by the Trinity House; but all vessels passing it pay the same rates as those received by the one on the Long Ships at the Land’s End, except coasting vessels, which pay only a shilling each. There is a small church on this island, the service of which is performed by a minister, appointed and paid by the Society for Promoting Christian Knowledge.