Hygroscope
Date
7 October 1663
Creator
Unknown, Artist
Object type
Archive reference number
Manuscript page number
p1
Material
Dimensions
height (page): 267mm
width (page): 203mm
width (page): 203mm
Subject
Content object
Description
Drawing of a hygroscope used to make measurement of the dryness and moisture in the air in a paper on weather by Robert Hooke. The instrument relies on a ripe wild-oat beard attached to a dial, which curls and straightens depending on the moisture in the air. Hooke indicates the dial should be created in the manner described by Emmanuel Maignan (Perspectiva Horaria (Rome, 1648), p. 89 and illustration).
Copies of this drawing can be found at RBO/3/001 and RBC/2/128.
Copies of this drawing can be found at RBO/3/001 and RBC/2/128.
Transcription
The description of Emanuel Magnan is as followeth;
Habet hygroscopium instar horarij mechanici versatilem Indicem
Transcribed by the Making Visible project
Habet hygroscopium instar horarij mechanici versatilem Indicem
Transcribed by the Making Visible project
Object history
At the meeting of the Royal Society on 7 October 1663, ‘Mr. Hooke’s paper concerning the observables for making a history of the weather was read, and ordered to be reviewed by the president and Sir Robert Moray, and then to be registered, and sent to the several persons, who had been engaged in this work of observing the changes of weather, as Dr. Power, Mr. Beal, etc.’ (Birch 1:311).
Figure printed in Thomas Sprat, The History of the Royal-Society of London for the Improving of Natural Knowledge (London: Printed by T. R. for J. Martyn and J. Allestry, 1667), p. 173.
Figure printed in Thomas Sprat, The History of the Royal-Society of London for the Improving of Natural Knowledge (London: Printed by T. R. for J. Martyn and J. Allestry, 1667), p. 173.
Related fellows
Robert Hooke (1635 - 1703, British) , Natural philosopher
Associated place