(1695) And amongst others I saw little worms which had well - nigh the same form as the worms that children void in their stools and whose thickness I judged to be about one fourth of the thickness of a hair from our head .Furthermore I saw Animalcules which stuck close together by their long tails , It appears from the title in the edition that the letter is addressed to Johann Wilhelm von Pfalz - Neuburg .See the Biogr .