Limerick writers have never had pretensions of being hit by the darts of the Muses, but have, instead, always come out, delightfully, to satisfy their delivery pangs (pun intended). Rubbing those with poetic sensibilities the wrong way with child-like glee, these promoters of udder side of literature have carved a no mean niche for themselves. Little wonder then, many a serious writers have often indulged in these silly, though pithy, little compositions.

While the origin of these poems is not clearly known, some claim that these were first used by soldiers returning from France to the Irish town of Limerick in the eighteenth century. But then, history never mattered insofar as to be of great relevance!

Bordering often on the obscene, limerick writers have never tried to defend their work as being totally clean & overboard. After all cleanliness might be next to godliness, it is nowhere near popularity. As has been right observed by one worthy:

A critic refused, as reviewer,
To read the obscene and impure;
He soon left the scene,
For the books that were clean
Just kept getting fewer and fewer.

The reasons for this too have been provided by limerick writers:

The limerick packs laughs anatomical
Into space that is quite economical.
But the good ones I've seen 
So seldom are clean
And the clean ones so seldom are comical

Obscenity or inanity has, obviously, not been the sole reason for the ever-growing popularity of limericks. But are these poems just nonsensical compositions by silly rhymesters? Certainly not! George Bernard Shaw had once said: 'Take the utmost trouble to find the right thing to say, and then say it with the utmost levity'. Who could have understood it better than a Limerick writer! Humor, undoubtedly, has to be the forte of successful limerick writers. Using hyperboles & puns with gay abundance, limericks try to floor the readers with their na've charm. Check out this masterpiece by an anonymous author :

A flea and a fly in a flue
Were caught, so what could they do?
Said the fly, "Let us flee."
"Let us fly," said the flea.
So they flew through a flaw in the flue.

Targeting the celebrities with glee, the limerick writers have tried to show the world, in their own simple way, that people on the pedestal too have clay feet. Here goes a limerick on a well known political scandal:

A Limerick I'm sure would be fun,
But I know the one here will not be the one
`cause the one I know will
is that one about Bill -
and Monica, et al, that I haven't begun.

(source: http://anitraweb.org/homelessness/columns/wes/9804.html)

Using limericks, some writers have even tried to do the impossible- tried to explain the esoteric principles through these silly poems! What would have been a better way of explaining the Theory of Relativity than this composition by A H Reginald Buller:

There was a young lady named Kite
Whose speed was much faster than light.
She left home one day
In a relative way
And returned on the previous night.

A mathematical gem by Professor Harvey L Carter reads:

'Tis a favourite project of mine
A new value of PI to assign.
I would fix it at three
For it's simpler you see
Than 3 point 1 4 1 5 9

Similarly, the following limericks by Robert D. Cowan selected by American Physical Society, provide a delightful insight into the laws of physics:

There once was a fly on the wall
I wonder why didn't it fall
Because its feet stuck
Or was it just luck
Or does gravity miss things so small?

Here is a limerick by Bruce Elliott mixing the profoundness of science with profanities of language with aplomb!

It filled Galileo with mirth
To watch his two rocks fall to Earth. 
He gladly proclaimed,
"Their rates are the same,
And quite independent of girth!"

Then Newton announced in due course 
His own law of gravity's force:
"It goes, I declare,
As the inverted square
Of the distance from object to source."

But remarkably, Einstein's equation
Succeeds to describe gravitation
As spacetime that's curved,
And it's this that will serve
As the planets' unique motivation.

Yet the end of the story's not written; 
By a new way of thinking we're smitten. 
We twist and we turn,
Attempting to learn 
The Superstring Theory of Witten!

Darwin could not have, perhaps, put this one better:

Said an ape as he swung by his tail,
To his offspring both female and male,
"From your offspring, my dears, 
In a couple of years,
May evolve a professor at Yale."

Poets might have had disdain for 'these rhymesters' for years, but at times they hit back, mocking at their abstruse serious writings:

There's a limerick writer called Wish:
There's Swift and there's Swoosh and there's Swish.
Swift's poems are bunk,
Swoosh's statues are junk,
And no one can understand Swish.

However, the beauty of limericks lies in double entendre & puns gingerly juxtaposed with other figurative forms of writing to deliver a powerful punch where it hurts most! Here's why Prof. Morris Bishop feels limericks should be quarantined:

The limerick is furtive and mean.
You must keep it in close quarantine,
Or she sneaks to the slums,
And promptly becomes
Disorderly, drunk and obscene.

Using the indelicate phrases with finesse, the limerick writers ensure that the readers are forced to smile. Quick witted and pithy , limericks often hit the nail bang on the head. What a Oliver Wendell Holmes has said for Man's compulsion to commit sins & still prevail can very well be said of limericks & limerick writers as well:

God's plan made a hopeful beginning,
But Man spoilt his chances by sinning;
We trust that the story
Will end in great glory,
But at present the other side's winning

Hate them or love them, limericks are here to stay. Long live the writers of five lined poems!

NOTE: The limericks quoted above have been collected from various sources, mostly from the Internet. Some of the links to the websites from where the limericks have been assorted are given below:

American Physical society: http://www.aps.org/apsnews/0397/11855.cfm) 
http://home.earthlink.net/~kristenaa/faves.html 
http://volweb.utk.edu/Schools/bedford/harrisms/limerick.htm
http://www.everything2.com/index.pl?node_id=452285.
http://www.ma.hw.ac.uk/~takis/etc/limericks_profs 
http://www.quotemountain.com/famous_quote_author/
oliver_wendell_holmes_famous_quotations/
http://www.angelfire.com/poetry/archielims/Limessay.html