image EL_L4_14_Fig
Image number: RS.15810
Credit: ©The Royal Society

Observations of the whittish matter on Van Leeuwenhoek's tongue after a fever


18 October 1707


Unknown, Artist

Object type

Archive reference number

Manuscript page number




height (page): 223mm
width (page): 173mm



Six figures. Drawn by anonymous draftsman.

Letter by Antoni van Leeuwenhoek to the Royal Society. Read at the meeting of 27 October 1708.

Fig. 1: particles scraped from his own tongue after a fever. AB was connected to the tongue.
Fig. 2: second particle from his tongue, with GH having been the connection to the tongue.
Fig. 3: a third particle from his tongue.
Fig. 4: more particles from the tongue, from which most branches are already rubbed off.
Fig. 5 and 6: the scales that lay around and over the particles shown in figs 1-4.

Object history

19 November 1707, 'A letter was read from Mr Leewenhoek concerning the whiteness of the tongue in fevers and thrushes. He was thank'd' (JBO/11/125).

A. Leeuwenhoek, ‘Concerning the whiteness on the tongue in fevers, etc.’, Phil. Trans., vol. 25, no. 312 (October, November and December 1707), pp. 2456-62, tab. 2, figs 1-6.

Related Fellows

Antoni van Leeuwenhoek (1632-1723, Dutch), Naturalist

Associated place

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