The orchestra's conductor Margaret Wright OAM explained that while the ensemble's annual excursion is really just ''a treat'' after months of rehearsals, an important inspiration for the recorder ensemble's annual musical voyage was the great occasion on the Thames in 1717.

Music that Handel had composed especially for the occasion was played for an enthralled King George I. His Majesty had sat in state in an ornate vessel moored on the river while 50 musicians on a barge went back and forth, playing. His Majesty was so delighted he commanded the suite be played a second and then a third time. Had there been some royal ears to listen on Wednesday it would have added to the verisimilitude.

But it was great fun anyway. With the engines of the waiting MV Southern Cross, purring gently at the wharf of the Southern Cross Yacht Club, the conductor took the ensemble, arranged inside the vessel's roomy cabin, through a rehearsal of the melody of the sombre hymn Eternal Father Strong To Save (For Those In Peril On The Sea).

The musicians had a good giggle about this. The old hymn is all about begging God to intervene to save those in peril out on the mighty ocean deep but earlier Knight had explained that it's a tradition they play this on excursion day.

''Sometimes we all fall about laughing and can hardly play,'' conductor Wright chortled yesterday ''because after all the lake is only like a mill pond''.

But it is this columnist's favourite hymn (with strong sentimental associations for me) and an unmanly tear threatened to appear in my eye as the ensemble piped it (twice) with great loveliness.

The word ''recorder'' will summon up for lots of readers those shrill, plastic, descant recorders we all played at school, but the instruments taken aboard were not at all like that.

Wright explained that it's not widely known that recorders (known and loved and much written-for by Handel, Bach, Telemann and other giants) come in eight sizes. Some of them are hefty in the extreme and have deep, sonorous voices.

Wright showed us one enormous one, a bass recorder, still only the third largest of the recorder range.

''Gosh, it's like a bazooka,'' this columnist marvelled.

''Or a didgeridoo,'' Wright corrected, gently.

Nor are these professionals' recorders ever made of plastic.

Two of Wright's own are made of rosewood and she explained that while there are no Stradivarius recorders the value of beautiful recorders depends on the fame of their makers and on the materials (one member of the ensemble has just come home from London with an expensive old recorder made from ebony and ivory) the instruments are crafted from.

Out on Lake Burley Griffin, the ensemble doesn't have an actual audience, other than a few family members, for its performances (save for the occasional appreciative swan) and only does it, Wright explains, ''Because it's a nice thing to play water music out on water.''

Wednesday's scheduled water music included not only Handel's fabulous composition but all sorts of ditties with watery themes, including the Beatles' Yellow Submarine and the grand Scottish air the Skye Boat Song, which of course urges the ''bonnie boat'' carrying the lad ''born to be king'' (the fleeing Bonnie Prince Charlie) ''over the sea to Skye''.

Actually it didn't need a major feat of the imagination, on a day of low cloud and driving rain, to imagine Lake Burley Griffin as the Hebridean waters across which the prince scudded in 1746 after defeat at the Battle of Culloden.

Cloud came down and blotted out Black Mountain's unattractive tower, giving the mountain a wild, unimproved, windswept, Hebridean look.

The weather for the water music voyage resembled the terrible weather that ruined London's 1749 sequel to the Water Music, the Royal Fireworks' occasion for which, again, Handel wrote a dazzling suite of music, this time to entertain George II.

Handel's music for that extravaganza endures but as a keenly-anticipated display of fireworks, the April 27, 1749, event was an extravaganza organiser's nightmare.

If Robyn Archer, the creative director of next year's Centenary shenanigans, has nightmares about what could go wrong at her biggest events those bad dreams will resemble the realities of 1749.

It was rainy night and lots of the fireworks fizzled, there was traffic gridlock on London Bridge and then the massive wooden tower from which the fireworks were to be launched caught fire and burnt to the ground.

The affable skipper of the Southern Cross, Brian Marriott, getting ready to sally forth, said that he'd skippered on these outings before and they were great fun, giving him the bonus of a free concert.

He was planning to take the ensemble out to the lake's Central Basin from where all of the great buildings were visible although in his experience the musicians were usually so intent on their music that they barely looked around them.

''They're lovely people,'' he enthused.

The only slight fault that he could find with them was that they were slow to adopt, to play on the voyage a favourite ditty of his, The Wreck of the Edmund Fitzgerald.