The Introduction of Self-Registering Meteorological Instruments

What, exactly, were the instruments applied by Hooke to his weather clock? It is not always easy even to guess, because it appears that Wren was actually the first to contrive such a device and seems to have developed nearly as many instruments as Hooke. It might be supposed that Hooke would have adapted to the weather clock his wheel-barometer, introduced in 1667, but it also appears that Wren had described (and perhaps built) a balance barometer before 1667.[10] As to the thermometer, we have no evidence of original work by Hooke, but we do have a description of Wren's self-registering thermometer, a circular, mercury-filled tube in which changes in temperat