'Only type of invention for which the U.S. Patent Office still insists on seeing a working model'
a perpetual motion machine
INVENTIONS: Only type of invention for which the U.S. Patent Office still insists on seeing a working model
Only type of invention for which the U.S. Patent Office still insists on seeing a working model
Only type of invention for which the U.S. Patent Office still insists on seeing a working model
INVENTIONS
a perpetual motion machine
INVENTIONS