Spithead!

In 1665 - 1666, the Bubonic Plague ravaged London, England. Cambridge University closed its doors for eighteen months. Isaac Newton, top of this class, returned to his childhood home of Woolsthrorpe Manor House. Hordes of feral cats roamed the streets. Isaac found a hungry black cat on this doorstep. He brought this cat inside and named it Spithead. At that time, cats were considered vermin: little better than the mice and rats they ate. Certainly, no one adopted them. The next months with Spithead were the most creative in Newton's life. He and his cat changed the world and revised all the laws of science. Then he invented something for his beloved Spithead that has endured for centuries. Today people call this invention the pet door.