My copy of Jeremy Lewis's entertaining 1996 memoir Kindred Spirits carries a hand-written dedication from its author. I won't reveal the name of the dedicatee, lest it cause any bad blood between him/her and Jeremy, the book having found its way to a second-hand shop in Oxford. 'Jezza' - as he is known to colleagues at The Oldie, where he is commissioning editor - has many friends in this city. He lived here for some years in the 1970s, having moved from London to join the staff of the Oxford University Press under Hugo Brunner, with whom he later worked in London for Chatto & Windus. (This column's congratulations to Hugo, incidentally, on his recent knighthood.) I feel pretty certain I must have met him at the time, since we were both regulars at the same pub, the Gardener's Arms, in Plantation Road.

"Not the last word on publishing," the dedication reads, "but I hope it makes you laugh." The same words could very easily be applied to Grub Street Irregular: Scenes from Literary Life (Harper Press, £20). This is the successor to Kindred Spirits and, as such, the third volume of autobiography (of a sort) that Lewis had promised (in a preface to KS) would not be with us until he was "well into my eighties". Well, oldie he may be, but not as oldie as that. By my calculation, he is still some two decades short of the mark.

The hugely entertaining new book continues in the same vein as Kindred Spirits, offering literary (mainly) gossip about people most of us have never heard of but are fascinated to be told about all the same. Derek Verschoyle, anyone? Or how about Peter Gunn, John Holroyd-Reece and Charles Fry? The last, the one-time boss of Batsford, was a drinker and lecher of legendary appetite. Lewis recalls how he told the wife of bookshop owner Heywood Hill that he had slept with three of her cousins, two male and one female, and he once returned from a publishing trip to New York claiming to have had sex with 40 people. Much of his legendary boozing, with the likes of Dylan Thomas and René Cutforth, occurred opposite his Knightsbridge offices in a pub called The Grove, in Beauchamp Place "where he might down 20 whiskies - this after a day drinking elsewhere - before hailing a taxi home." As a one-time habitué of The Grove myself, I was interested to learn of all this debauchery occurring on the premises. My abiding recollection is of an afternoon drink there during which I was complimented by a friend on the attractive brooch I was wearing. Suddenly the 'brooch' moved on my lapel. It was a large, glistening cockroach.

The diarist James Lees-Milne had much to tell us about Fry. A wartime entry (quoted by Jeremy Lewis) reports: "I had lunch with Charles Fry at the Park Lane Hotel. He was late, having just got up from some orgy à trois with whips, etc. He related every detail . . . In the middle of the narration I simply said 'Stop! Stop!' At the next table an officer was eating and imbibing every word. I thought he gave me a very crooked look for having spoilt his fun."

As a long-term admirer of Lees-Milne, Lewis supplied the foreword for a reprint of his autobiography, Another Self. This has been recycled with little or no alteration to become the appreciation of Lees-Milne that appears in Grub Street Irregular. The effect of this has been to give a new lease of life to a myth, as it appears to be, concerning an episode that allegedly led to Lees-Milne's lifetime of work for the National Trust. This concerned a visit he says he made as a Magdalen College undergraduate to Rousham, the lovely William Kent house beside the Cherwell, where he witnessed an orgy of destruction involving its tenant and his friends - paintings attacked with a riding crop, for instance, and pot-shots at the garden statues. From that moment he decided to dedicate his life to preserving the "infinitely fragile and precious" buildings of England.

But when mention was made of Rousham in the last volume of Lees-Milne's diaries, The Milk of Paradise, published in 2005, editor Michael Bloch commented in a footnote respecting JLM's claim: "This has been questioned by some contemporaries, and he never mentions the alleged incident in writing about Rousham in his diaries." So did it actually happen? Earlier in the week I put this question to Mr Bloch. He kindly took the trouble to reply, as follows: 'I don't think there's any doubt that the orgiastic dinner party at Rousham took place. (The host was Maurice Hastings, see Vol.1 of Bevis Hillier's life of Betjeman.) The question is whether JLM was present, or merely heard about it from friends. He had a very active imagination and it would have been a short step for him from imagining how he would have felt if he had been there, to imagining that he actually had been. When Another Self appeared in 1970, the late Sir Roy Harrod told his wife and various friends that he was there and Jim wasn't. The fact that Jim, in referring to Rousham in his diary, never recalls the episode which took place there and allegedly changed his life leads me to suppose that Harrod was correct. Of course, it's quite possible that just hearing about it was a damascene event as alleged."

Next month sees the centenary of Lees-Milne's birth. One event marking the occasion will be the publication of a third volume of his diaries, edited by Mr Bloch, by John Murray. Another will be an exhibition devoted to him at St Katherine's Church, Chiselhampton, by calligrapher Andrew Moore. This runs from August 2-10, and is open from 10am to 4pm.