Yes, there is discussion of his music, the 40th anniversary world tour of the progressive rock classic "Thick As A Brick", and of its 2012 follow up. But there is also a lot more about flutes in space, an unlikely link with the George W. Bush White House - and the importance of prostate examinations.

Anderson, now 64 and dapper rather than the frenzied druid-cum-warlock of yore, is quite clear and animated about the latter. Too many family and friends have died from prostate and colon cancer for him to ignore it.

So much so, in fact, that his current world tour - taking in most of Europe, Israel and more than two dozen stops across the United States -includes a full-fledged skit on the subject, a rallying cry for the audience to get checked plus a visual reminder of those felled by the condition, including cult musician Frank Zappa.

"It is a very serious message," Anderson told Reuters over a beer in railway station pub recently. "If I can get two (in the audience to get a check), I can save lives."

Not that any of this should be taken to suggest that Anderson's current "Thick As a Brick" concerts are overly serious or message-laden. On the contrary, they are a joyful celebration of all that was 1970s prog rock - over-the-top navel-gazing mixed with often sublime musicianship.

A lot of this was evident at a recent, packed concert at London's Hammersmith Apollo, where Anderson was backed by a tight band that included a remarkable sound-a-like singer to help him through the double-tracks of the original.

With impressive agility and age-defying lung power, Anderson cavorted across the stage, keeping the trilling and tutting on his flute going for a couple of hours and leaping from time to time into his trademark one-legged stance.

Some of the rock bite of early Jethro Tull was missing, but it was a crowd-pleaser nonetheless, as was the second half of the show, a performance of "Thick As A Brick 2", a new work bringing the 1972 story into the 21st century.

BOSTOCK REVISITED

Anderson's original "Thick As a Brick" was actually a mild spoof of the prog albums of the time, a response to critics who had labeled Jethro Tull's earlier rock best-seller "Aqualung" as a concept album - something Anderson denies to this day.

But the album, which tells the tale of eight-year old Gerald Bostock who has purportedly written an epic poem, soon entered the pantheon of prog albums.

Its record cover alone, a pretend St. Cleve Chronicle and Linwood Advertiser newspaper, was on the cutting edge of an art form that has all but disappeared with CDs and MP3s.

"It was very much a parody of the prog rock genre of the time," Anderson said. "Some people got it. Some people didn't."

The show - for that is what it is rather than just a concert - brings in video projections, skits and spoof YouTube broadcasts, most of which would have been unthinkable when the original was being cut on vinyl.

This fits well with second half performance, the follow-up work subtitled "Whatever Happened to Gerald Bostock?", which looks at how the young poet may have fared 40 years on - banker, soldier, homeless man, ordinary bloke?

Musically, it is entertaining and carries the listener away as any good prog should. A Billboard review went as far as to say it proves "there are still vital sonic statements to be made within the old-school prog-rock realm".

But enough of music. Anderson talked about a broad range of subjects, including his late friend Tony Snow, the George W. Bush White House spokesman who died of colon cancer - another motivation for his one-man campaign for regular health checks.

They met when Snow, an amateur jazz flautist, was a television journalist. Anderson reckons it was Snow, not himself, who was parodied in the film "Anchorman" when the character Ron Burgundy jumps on a stage and does a crazy flute solo.

Proudly, he also talks about how U.S. astronaut Catherine Coleman took his flute to the International Space Station with her - a third of her personal allowance.

Anderson and Coleman played a duet via video link on the 50th anniversary of Yuri Gagarin's first-man-in-space flight last year.

The Space Flute, as it is dubbed, is now safely on Earth.

(Reporting by Jeremy Gaunt, editing by Paul Casciato)

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