The Lorentz contraction is also called the Fitzgerald contraction or the Lorenz-Fitzgerald contraction. It is caused by relativistic effects seen between observers moving toward or away from one another. The size of one object as seen by someone moving toward or away from it it is decreased along their line of movement by an amount mathematically related to their speed and the speed of light.
In his book, One, Two, Three...Infinity, physicist George Gamow quoted a limerick (a kind of poem) that is said by some to have been changed from a more naughty poem. There are several other cleaned up versions: