The Royal Society decided to send a gift to Leeuwenhoek

May 19, 1686

The Royal Society had trouble enough publishing Philosophical Transactions regularly. They rarely ventured into book publishing, though in the mid-1680's, they financed the production of De Historia piscium (The History of Fishes) by Francis Willughby and proposed to finance Newton's Principia. However, History of Fishes didn't sell well and Halley ended up getting paid with leftover copies rather than cash. This was after he ended up financing Newton's Principia out of his own pocket.

The total cost of printing History of Fishes on the best paper (22 shillings per ream) and the worst paper (15 shillings per ream) was 360 pounds. Two thirds of it was spent on the engravings. The one on the right shows a whiting.

By May of 1686, the Royal Society was giving copies to some of their foreign members.

It was ordered, that signor Malphighi, Mr. Hevelius, Mr. Leewenhoeck, and Mons. Bayle be each of them presented with one copy of Mr. Willughby's History of Fishes.

Leeuwenhoek responded to this gift in his next letter, Letter 51 of June 10, 1686.