Rock star Phil Lynott was recording his second solo album in a studio in Soho and, as usual, the control room was overflowing with hangers-on.

Lynott made a show of conducting a headcount - 12 people. Gazing at the expectant entourage, he carefully prepared 12 lines of cocaine. And then he snorted them all himself.

"He sat next to me and clenched the edge of the desk," says the producer, Kit Woolven. "His hands went pure white, he was holding the desk so tightly."

The gesture was both a rebuke to the freeloaders and a characteristic display of machismo. Lynott - Ireland's first bona fide rock star and one of popular music's most notorious hellraisers - always prided himself on his ability to drink more, snort more and generally be more rock 'n' roll than anyone else.

The story is recounted in Cowboy Song, the first ever authorised biography of Lynott, published to coincide with the 30th anniversary of the singer's death at the age of 36. Head and shoulders above the usual rock hagiography, the book is by the well-respected music writer Graeme Thomson, who won huge acclaim for his examination of the life of Kate Bush in 2010.