On 15 August 1812, Bell's ship began a passenger service on the River Clyde, connecting Helensburgh to Greenock and Glasgow.

[5] On 15 August 1812, Bell advertised in a local newspaper "The Greenock Advertiser", that the Comet would begin a regular passenger service from that day, a distance of 25 miles (40 kilometres) each way:[7] The Steamboat Comet Between Glasgow, Greenock and Helensburgh for Passengers Only The subscriber, having at much expense, fitted up a handsome vessel to ply upon the River Clyde from Glasgow, to sail by the power of air, wind, and steam, intends that the vessel shall leave the Broomielaw on Tuesdays, Thursdays, and Saturdays about mid-day, or such hour thereafter as may answer from the state of the tide, and to leave Greenock on Mondays, Wednesdays, and Fridays in the morning to suit the tide.On 15 August Comet made the first commercial sailing from Glasgow for Bowling, Helensburgh and Greenock, opening the era of the steamboat on the Clyde, and more widely in Britain and Europe.

Bell had the Comet lengthened and re-engined, and from September 1819 ran a service to Oban and Fort William (via the Crinan Canal), a trip which took four days.

The Glasgow Herald reported a piece from the Greenock Telegraph which stated "part of the hull of the Ann was all that was left of Henry Bell's old Comet, the first steam-vessel ever to sail in European waters.

The curious thing is, that having been built at Port-Glasgow 63 years ago, and undergoing many vicissitudes, she should, like an old weather-beaten sailor, end her days almost at the threshold of her own home.

"[9] Bell built another vessel, Comet II, but on 21 October 1825 she collided with the steamer Ayr off Kempock Point, Gourock, Scotland.

The Captain and passengers immediately ran upon deck to see what was wrong; when – the next fatal stroke took place with such force, that the Comet filled, and in two minutes went down head foremost.

The moment this look place, the Ayr, instead of lending any assistance, gave her paddles a back stroke, turned round, and went off to Greenock, leaving them to their fate.Comet II sank very quickly, killing 62 of the estimated 80 passengers on board,[8] including the son-in-law of John Anderson, a friend of Robert Burns.

[11][4] As part of the anniversary celebrations the replica sailed from Port Glasgow to Helensburgh and back, accompanied by a flotilla of small ships.