I love the Monty Python sketch “Stake Your Claim”.

It is extreme, but then it is Python.

John Cleese is a game show host investigating preposterous claims made by contestants. I think, loosely, that if your claim is proved sound, you win. But as with most Python there is plenty left to our subconscious to guffaw at.

We arrive mid-show, just as Michael Palin is staking his claim that he wrote all Shakespeare’s plays, while his wife wrote all his sonnets.

Well, says the host, testingly: the plays were performed n the early 17th century. How old is the claimant?

43, it appears.

So how is it possible that the claimant wrote the plays 300 years before he was born?

That, says Palin, is where his claim falls to the ground. He is escorted offstage peremptorily.

Then Graham Chapman appears dressed as a lady of a certain age named Mrs Mittleschmerz. When asked what his claim is, he intones in that unmistakable pepperpot tone: “That I can burrow through an elephant.”

There is a short uncomfortable silence. It appears the lady has changed her original claim, which was that she could be thrown off Beachy Head, a very high cliff here in the UK.

Burrowing is preferable to a variety of undesirable outcomes.

As any self-respecting rabbit will tell you. Rabbits come out when there is nobody around to nibble grass and take the air with friends and family and acquaintances.

But the moment I draw up in my great big car and create some good vibrations, they are but a cloud of dust in a warm June evening. Off to the burrow for shelter.

I used to love to watch my good friends the gerbils burrow in the simulated desert burrow created out of plastic in my old bedroom at the ancestral home.

They  seemed to buy the dream that they were burrowing in time-honoured fashion, as their forebears did in the sand-burrows of old. And when someone walked into the room up would go the alarm, and they would bolt, as one gerbil, down into the spacious seventies-style Space 1999 modules at the base of the unit: a veritable gerbil command centre which was, as far as they were concerned, deep beneath the desert sands in the cool of shady subterrania.

I wonder if they ever thought: hold on, who let that daylight in here?

Rotastak have become ever more lavish and ambitious with their homes for little scuttlers. I believe one of their proudest days saw the advent of the Rotastak Creepy Castle. Mind boggling, I searched for a picture of this new way to live the burrowing dream, Hallowe’en style.

It has mediaeval walls emblazoned on the seventies style modules, and reminded me strongly of a film called The Man With Two Brains, where a mad scientist lives in a condominium which looks for all the world like a Norman castle.

The walls in the condos, regrettably, are paper-thin and one can hear the neighbours arguing.

There are burrows beneath the earth in England: in Wiltshire and in the cliffs of Kent, they used to guard national secrets. When the going gets tough, apparently, the tough get burrowing.

Burrowing, however, is not always an escape. Occasionally one wants a home.

Like Bilbo Baggins. The furry-footed Hobbit had the most beautiful burrow. Tolkien writes: “Not a nasty, dirty, wet hole, filled with the ends of worms and an oozy smell, nor yet a dry, bare, sandy hole with nothing in it to sit down on or to eat: it was a hobbit-hole and that means comfort.”

Tolkien is said to have modelled the little burrow on his own house in Northmoor Road, Oxford. It was a place which meant comfort.

There are other motivations to burrow and tunnel.

Jules Verne is such a distinct voice of early science fiction. His hypotheses have not stood the test of time, but his stories still make rollicking good reads.

The spirit of adventure was strong in him. One biographer circulated a rumour that the young Jules stowed away on a ship bound for the West Indies, in a bid to go and meet adventure in person; but the liaison was called unceremoniously off when his father made for the next port, and took him home.

It burns brightly in his tales, though. Journey To The Centre Of The Earth – published in 1864 – hypothesised that there were volcanic tubes along which one could travel, right through the sphere and out the other side. And on the way, Verne wove a parareality in which one might encounter different periods of the earth’s development, complete with those who might have inhabited them at the time.

Verne created the possibility of subterranean civilisation.

And so did CS Lewis.

I am drawn again and again to the volume of his Narnian chronicles which looks not within Narnia, not to far distant lands, but deep within the earth.

The land of Bism, of which I have spoken before, is a greater metaphor than almost any other I have come across. I’ll recap briefly: CS Lewis created  a world which had three layers: the top layer, where man dwells: the middle layer, where a cruel witch rules and keeps a Narnian prince captive with magic; and the earth’s core.

The workers in the middle world are sallow and dull, right up till the moment the middle world and its magical construct crumble. And then it is revealed these workers were born in the earth’s core: a wondrous place where  diamonds come from. There, they grow on trees. Those dead diamonds in our earth’s crust, the tale runs, they are just shadows of the real thing.

The burrow: a bolthole from that bolt out of the blue, a Seventies gerbillian illusion, a symbol of comfort, or a path to adventure. We’ve looked at it from many perspectives.

But Lewis: Lewis turned the whole burrow upside down. While the surface of his world, and its subterranean workings, can only hold empty lifeless carbon, it is the fiery core, suffused with joy and animation, which brings true living diamonds.

I wonder if he was trying to tell us something?