Underground London

I always wanted to know what went on in that disused tram tunnel in Kingsway...

That and many other facts are are the stuffing of Stephen Smith's Underground London, a book that has left me feeling that I spend my days patrolling the capital's mezzanine floor. It has been written in the ephemeral style of the newspaper journalist, with amiable, self-deprecating humour, rather like a soft-pedalling Tim Moore.

Like myself, Smith can trace his childhood ambivalence towards subterranean spaces to the Moorgate tube crash of 1975 in which 43 people died.

He also recalls the Hole in the Wall pub on the platform at Sloane Square (last orders in 1985) which features in Vile Bodies and mentions the big metal pipe which still traverses the station above the platforms - the long lost river Westbourne.

He visits the silver market and vaults in Chancery Lane, beneath a building in which my company's accounts department were briefly exiled in the 90s. He finds that the people that try to brighten their lives with "costly, shiny, pointless stuff" are more obviously melancholic than the cheery-cheeked folk down in the cellars of Berry Brothers & Rudd, who regularly participate in the "drawing room farce of wine appreciation."

He hangs out with some corpse lifters at the church of St Andrew's located next to the glass-house fronting of the Sainsbury's HQ close to Holborn Viaduct which spans the valley of the hidden river Fleet. This house of God once sat proud and alone atop 'Heavy Hill', down which early modern ASBO types used to roll old ladies in barrels.

He joins the monomathematical society known as Subterranea Britannica and at one of their gatherings listens to a keynote speech by Duncan Campbell, the journalist who one evening back in 1980 managed to get himself (and a bicycle) through a manhole cover near Bishopsgate and proceeded to tour the hushest of the hush - the 20+ miles of tunnels that link up the ministeries with other underground government control centres. Smith discovers that the biggest barrier to composing a guide to this secret complex is that there are basically two types of people: "Those who enter the government labyrinth and don't write about it, and those who write about it but don't enter it".

He warns us that the Thames Barrier is being raised in anger ever more frequently these days, and that there are forty effluent overspills from the sewers into the river each year. He recounts how a major flood back in 1236 resulted in the use of rowing boats inside Westminster Hall.

There are plenty of other fascinating facts to soak up here. Here's my own annotated list of the more memorable:

• Oysters were a poor man's dinner up to and including Dickensian times.
• Battersea park can get seriously whiffy because there's a major sewer directly beneath it.
• If you step on a dead rat it "goes off like a Chicken Kiev". Dead bodies also tend to explode in their coffins.
• Nelson's body was preserved in brandy. Some explosion that would have been.
• Calls for Inspector Sands on the PA system are London Transport's way of announcing an emergency to station staff without creating passenger panic in the tunnels.
• The gunpowder laid down by Guy Fawkes would have blown up the Palace of Westminster 25 times over. It would also have taken out the Abbey and most of Whitehall.
• Mount Pleasant was given it's name by someone with a sarcastic bent- unlike Guatemala's El Progreso and France's Nice where the irony was clearly unintentional.
• Houndsditch meanwhile was the place all the dead doggies ended up. Kentish Town? Let's not go there.