The makers of this extraordinary stuff, A Hormel and Company, of Minnesota, are organising Spam contests to mark the occasion, and this seems fitting.

I recall a friend of mine telling of the horror on the face of his father during the war years when he returned from work and found his family at the tea table munching Spam sandwiches.

"What are you doing?'' he cried. "Spam is for buying and selling, not for eating!''

My research tells me that during the war the attics of Liverpool houses were chock-a-block with Spam that had been nicked from the docks.

At that time, there were four units of British currency: pounds, shillings, pence and Spam. This, of course, gave rise to the old proverb: "A fool and his Spam are soon parted.''

The great advantage that Spam has over food is that it is waterproof and can be eaten in the shower. Sliced, it also makes excellent tiling for roofs.

There are so many things you can do with Spam that you cannot do with, say, corned beef. If you fry corned beef, it falls apart, but Spam doesn't. It exudes a strong glue which welds the Spam to the pan.

It was this quality that triggered the invention of the Spam limpet mine, responsible for the sabotage of so many German vessels during WW2.

In 50 years, a staggering four billion tins of Spam have been shuttled around the world. If they were all gathered together and dumped in the Atlantic,the entire land mass of the planet would be swamped, therefore it would be better to fire them into space and let them join the other detritus up there.

The prospect of tins of Spam circling the heavens is appealing to we poets. Lovers could say "Darling, there's a full tin of Spam out tonight,'' and I dare say we could bounce television programmes off them.

How different from the original intention, which was simply to feed and amuse people simultaneously. If you look closely at pigs, you will see they are still laughing.