Mimsy were the Borogoves
Author: Henry Kuttner
Year: 1943
Millions of years in the future, a post-human scientist experimenting with a
time machine sends two boxes with hastily gathered batches of educational toys
into the past. The first arrives in the middle of the twentieth century and the
second in the latter part of the nineteenth century. Believing the experiment
to be a failure when the machines and test objects fail to return, he
discontinues his efforts. […]
(Wikipedia)