I built a time machine
left it on a bench
in 1917
bottom of a trench

the next worked fine
sweetly constructed
lost in 79
when Vesuvius erupted

improved version three
I left in the brig
of an interplanetary
mining ship

four’s long gone
wrapped in a liner
when Genghis Khan
invaded China

it’s always the same
my invention’s hot
it’s just a shame
my memory’s not