Letter, from Antoni van Leeuwenhoek to the Royal Society, dated at Delft Signed autograph On the spermatozoa of spiders Read to the Royal Society on 28 January 1701 English translation see EL/L3/41 Transcribed in JBO/10/238 Transcribed and translated in 'Alle de brieven van Antoni van Leeuwenhoek', edited, illustrated and annotated by Committee of Dutch Scientists, vol 14, p 47 English translation printed in 'Philosophical Transactions', vol 23, no 279, p 1141 20 December 1701