Translated extract of a letter, from Antoni van Leeuwenhoek to the Royal Society Observations of the seeds of cotton, palm or date stones, cloves, nutmeg, gooseberries, currants, tulips; observations of the skin on the hand, and sweat pores, the crystalline humour and optic nerve of a horse, the gall and scales of fish Printed in 'Philosophical Transactions', vol 17, no 205, p 949 nd