Library: British Library, London

Manuscript: Sloane MS 4041

Folio: ff. 67-68

Microfilm: The History of Science and Technology Series One: The Papers of Sir Hans Sloane, 1660-1753 From the British Library, London Part 1: Science & Society, 1660-1773 Reel 3 Sloane Mss. 4040, 4041 98462

Language: English

Letter Categories:
Curiosity Reports
Philosophical Transactions
Royal Society

Letter Subject:
Flying Ants

Date of letter (as written): November 17, 1707 (Gregorian)

Standardised date: 1707-11-17

Letter Origin (as written): Upminster

Letter Destination (as written): To Dr Sloane at his House in Bloomsbury-Square London

William Derham

Sir Hans Sloane

Others Mentioned:
Mr. Barret
Mr. Culverwell

Letter written about self or others: N/A

Single or Multiple Sufferers: N/A

Patients Mentioned in Letter:
No Patients Attached to this Letter


[fol. 68] Sr Upminster Nov 17 1707 Your Lr to Culverwell & sent the next day by our Penny-Post. I was lately at our friend Mr Barrets, who desir- ed me to acquaint the Society concerning the Flights of Ants (yt made such a noise in London last Sumer) That he hath for many years last past constantly ob- served the Flight of that Insect on the very same, or within a day or two of that very day of the Month, on which they fell in London. About the year 1689 or 1690 (as I remember) he said he saw a cloud of them, and several times since he hath seen the same. He took it for a Cloud full of Rain approaching towards him, & was much surprized to find it a vast Number of Ants only frisking in the Air, & carried alonf as he imagined only wth the gentle Current of the Air. He is of opinion that they allways come fromward the Westerly points. I hope our curious Members will for the future observe them more accurately, yt we may make a judgment from what parts they came. The next day after they fell in London, I remember we had in divers places many of them, particularly at Mr Bar- rets, & South-Weal & Burntwood. I call them Flying- Ants, because Mr Barret (who is a good Judge) said they were such yt he saw. I long much to have the opinion of you, & other such curious persons what those in London were because a few days after on the top of the Observatory, at Greenwich, as I was taking some Angles. I met with a great company of small brown ichneumons somewhat resembling those bred in Briar-Balls. Another thing Mr Barret was willing the Society should know is a Notion he hath of Pit-coales being generated from rotten vegetables in moorish Lands. He hath divers curious observations about this matter, wch I endeavoured to persuade him to draw up for the use of the Society, as also to have given his own account about the Flight of Ants. But his modesty suppresseth these, & divers other of his curiousities, wch I believe he would at your request impart to you in writing. At this very time I am writing, a larg Spot is on the utmost brink of the Sun going off; & another is advanced there or some-days stages on the Eastern Limb. This latter spot I saw somewhat of, the last revolution of the Sun on his own Axis. I saw it from a Spiss Spot fade, & at the Western Limb became a Facula. And now at its second appear-ance on the Disk, it was at first a Facula & the Spot very languid in the middle of it. But as the Facula went off, the Spot grew darker. But I shall say no more of it, by reason I am drawing up an account, wth many observations, of all the spots yt have appeared on the Sun ever since 1703: which have been very frequent. Not being at leaisure to pay any respects in person, I hope this tender thereof in writing (although drawn up in great hast) will be acceptable to the most illustrious Society, & to you Self from Sr Your much obliged humble servant W Derham

Other Notes:
Derham was a Church of England clergyman and a natural philosopher, interested in nature, mathematics, and philosophy. He frequently requested medical advice from Sloane, and likely served as a physician to his family and parishioners (Marja Smolenaars, "Derham, William (1657-1735)", Oxford Dictionary of National Biography, Oxford University Press, 2004 [, accessed 7 June 2011]).