Graphical details: the secret life of Christopher Wren's drawing of the weather clock

Ion Mihailescu

doi:10.1098/rsnr.2021.0048

Abstract

Historians have unanimously credited Christopher Wren with having constructed a weather clock (a self-registering instrument) in the early 1660s. This conclusion was based on the account of the French diplomat Balthasar de Monconys, which included a sketch uncannily similar to an undated drawing by Wren of the weather clock. By critically re-examining the available sources, I argue that one can infer that Wren never actually constructed a weather clock. What Monconys saw and sketched was, in fact, a drawing produced by Wren for a meeting of the Royal Society that took place on 8 January 1662. I further show that there is strong evidence to assume that Wren's drawing for the Royal Society is the undated drawing preserved at the Royal Institute of British Architects. The new context in which I place Wren's drawing provides an incentive to look at it with fresh eyes. Though the drawing does not represent a device actually constructed by Wren, it still bears (unexpected) connections to the material world that surrounded him. The analysis of the drawing developed in this article will be relevant for historians interested in the role that images can play as historical evidence.

Highlights

Historians have unanimously credited Christopher Wren with having constructed a weather clock in the early 1660s. This conclusion was based on the account of the French diplomat Balthasar de Monconys, which included a sketch uncannily similar to an undated drawing by Wren of the weather clock
After describing what was depicted in the drawing, Wren ended the letter with a note about what the Society might expect to find in this scheme: ‘I have willingly in this last contrivance omitted the Boxes, because I thinke they may be better disposed themselves; & I doubt too whether they would not be drie, ere the observer comes to looke in them.’
Why not choose more obvious and well-established graphical conventions, such as an exploded view or a cutaway?69 Unlike drawings or prints of machines that had to be intelligible on their own, or that belonged to well-established genres with particular styles and conventions, Wren’s drawing was made for a unique occasion: an oral presentation

Summary

Mihailescu

Sketch’, and that it might only show a ‘sealing-wax and string model’, W. Visual culture and the graphical practices of the early modern period, this paper is focused on the close analysis of a single drawing or, even of details of a drawing This narrow choice of focus is deliberate and is a provocation to historians to look at images as scientific objects and as forms of historical evidence. My goal is not to use textual sources to explain the image, but rather to produce unknown and unexpected results about the drawing’s surrounding world that I can corroborate, or at least make plausible, using textual sources This will allow me to connect Wren’s world of paper to the material world that surrounded him and that is reflected not so much in the objects that are represented (weather glasses, clocks, etc.) but rather in small graphical details, which are passed over as insignificant ornaments when regarded in isolation, but which can Astron. Though the records of the Royal Society do not make an explicit reference to Wren’s address, the minutes of the meetings for the month of January 1662 include the following relevant entries:

January 22 January

CONCLUSION