In 1909–10, William G. Allen patented a method of cold-forming screw heads around a hexagonal die. The tool for driving such screws is now known to engineers as an Allen (or hex) key. It comes in different sizes and is easy to use, as a certain grandson has demonstrated.
Our Neolithic ancestors made tools of flint and bone
As they hadn’t worked out how to extract metal out of stone.
The Bronze Age, then the Iron age, came; and then, eventually,
The human race invented the amazing Allen key.
A simple bar of iron, bent one-fourth1 along its length,
Lets you tighten socket screws without excessive manual strength.
And I have seen a one-year-old pick up an Allen key
And put it in a socket head – and do so easily.
The next stage of young Joseph Judge’s Allen-key enlightening
Is: “Long end in for spinning down, and short end in for tightening2”.
In years to come, when fully trained, what wonders might we see
As Joe grows up and wields his own amazing Allen key?
1 It’s roughly a quarter. (If one end becomes rounded with use, grinding a few millimetres off the length produces a fresh new hexagonal end!)
2 At a more advanced level, he’ll learn that the different arm lengths can give you useful access options, too.