The history of the rubber duck is not completely definitive. Though it's
linked to common use of rubber by the end of the 19th century to manufacture
all sorts of household items, there is a lack of hard evidence pointing to a
distinct "first" rubber duck. So far as we can tell, Jodie Davis, author of
Rubber Duckie, has the definitive documentation on the history of rubber ducks.
All we can say is, check out her book. And, what’s better than this: if you buy
the book new, you get a rubber duck with it!