This child's toy was built by young Holmes Somerby, grandson of inventor and engineer Ralph J Somerby.  Young 
Holmes likes to spend time in his grandfather's workshop, enjoys watching over his grandfathers shoulder and
learning all about engineering. This toy was made from spare parts Holmes found in the workshop. As young Holmes
says with great excitement in his voice "you hold on to it here [differential gear case] and spin it around"
while showing you with his hands how it spins around.