Anthonie Heinsius wrote Letter L-133 to Leeuwenhoek about recent observations of generation

This letter is known only by reference in another letter. Heinsius writes from Paris that he and several of his colleagues are pleased by Leeuwenhoek’s observations. He wrote from Paris because after the Peace of Nijmegen in 1683, Stadtholder William III of Orange-Nassau sent Heinsius on a mission to Versailles to negotiate the status of the principality of Orange, of which William III was sovereign prince but which was then occupied by Louis XIV.

Leeuwenhoek was probably referring to observations that he wrote to the Royal Society about in Letter L-128 of 16 July 1683 to Christopher Wren, a copy of which Leeuwenhoek had sent to Heinsius under cover of Letter L-129 of 22 July 1683. He had sent a copy of that letter to Heinsius. His letters to Heinsius in May, July, and earlier in September show his concern over how the Royal Society would receive his observations and ideas about generation.