Joseph Jérôme Lefrançois de Lalande was the editor of the French Connaissance des Temps and a friend and collaborator of Nevil Maskelyne and other English longitude actors. Recently I noticed that in Lalande's diary from his 1763 visit to England - during which he viewed the marine timekeepers of John Harrison - he recounted an unusual comment made about one of his colleagues.

On Easter Saturday 1763, Lalande recorded that the Astronomer Royal Nathaniel Bliss said 'that Mr Lemonnier attached the wire to his quadrant with wax from his ears, that he went to Oxford with his sword broken, and that his observations agree less well with those of Mr Bevis than those of Caille.' Pierre Charles Lemonnier or Le Monnier was a talented French astronomer 17 years Lalande's senior who had a penchant for British instruments and astronomical methods and was a member of the Royal Society and the French Academy of Sciences. His quadrant was made by Jonathan Sisson, a well-known London instrument maker whose son Jeremiah made Christopher Irwin's marine chair in the late 1750s and unsuccessfully sought a reward from the Board of Longitude in the late 1760s.

Are the statements attributed to Bliss a neutral record of Lemonnier's characteristics and of his approach to using instruments - with the earwax method just being another of the ways in which individuals worked out how to use or adapt or repair their instruments? Or was the entire statement intended as a slam against the older astronomer's abilities but also his gentility? A sword was an important symbol for an early modern 'gentleman' - even if by 1727 César de Saussure said that the label was ‘usually given to any well-dressed person wearing a sword’ in England - and Lemonnier's was said to be broken.

Although Lemonnier had helped to launch Lalande's astronomical career, the two astronomers fell out for years - either over the former's temper or over the latter's indiscreet manner of correcting his colleague's errors, according to different sources. It would be fascinating to know - perhaps someone out there can help? - whether this was just another round in their disagreement or whether Lemonnier really did incorporate his earwax into his astronomy.

Fig. 40, 'Tidens naturlære', Poul la Cour, 1903 - Wikimedia.