For Want of a Nail

For want of a nail the shoe was lost.
For want of a shoe the horse was lost.
For want of a horse the rider was lost.
For want of a rider the message was lost.
For want of a message the battle was lost.
For want of a battle the kingdom was lost.
And all for the want of a horseshoe nail.

For Want of a Valve Stem

For want of a valve stem the tire went flat.
For want of a tire the propeller was damaged.
For want of a propeller the engine has to be torn down.
For want of an engine the airplane may be declared a total loss.
And all for the want of a valve stem.