Pp. 46, frontis plate, 18 plates of photographic reproductions of the letter. Quarter red cloth over printed blue boards with title lettered in red, sm folio (31.5 x 24 cm). The subtitle of this work is: "A photographic copy of the letter of the 9th of October, 1676 sent by Antony van Leeuwenhoek to Henry Oldenburg, secretary of the Royal Society of London and a translation into English by Barnett Cohen". In addition to the translation of the letter, the translator, B. Cohen, also provides a long essay on the significance of the letter. An original engraving from 18th century illustrating a portrait of Leeuwenhoek is laid on at the front (this was inserted by a former owner).