Shamrock was built by Nathaniel Shepherd, Boat and Yacht Builder at Bowness-on-Windermere in 1906.

Originally was fitted with a Sissons triple expansion steam engine, she was owned by W.M. Birtwistle. In 1929 she was acquired by Mr Birtwistle’s boatman Charles Ashley, who ran the boat between 1930 and when she was taken over by his son William (Billy) Ashley, until he and other local boat owners formed the Bowness Bay Boating Company and Shamrock became part of that fleet.

In 1948 Billy Ashley removed the engine and boiler, converting her to a motorboat for the purpose of using her for boat trips on the lake. By 1974 she was laid up and her future was uncertain and by 1976 her condition had deteriorated badly. However, inNovember of that year Roger Mallinson acquired Shamrock and between 1976 and 1979, instituted a major restoration and conservation programme before installing a new steam engine (Number 5) and adapting a suitable boiler.

From this point onwards Shamrock became an instantly recognizable and much-loved feature of Windermere and took part in its many celebrations, musical evenings, rallies and parades.

The Engine

The two cylinder, double high pressure engine currently in Shamrock was built in 2001 by Roger Mallinson and was his 32nd engine – numbered 3201. It has 4 turned steel columns with Marshall valve gear working both slide valves in one valve chest at the back of the cylinder block. Cylinder bore is 4" (100mm) + 4" and the stroke is 5" (125mm).

The inspiration for both engines, No5 and No 3201, came from a duplex steam pump and details from the original triple expansion engine by Sissons (also with Marshall radial valve gear, with a similar engine is installed in Swallow, a sister launch). The rear crank bearing is deliberately large so it can be used as the thrust bearing for the propeller shaft. All the design characteristics are based on achieving silence and reliability.

The Boiler

Locomotive type boiler, built in 1927 by Yorkshire Engine Co. Ltd. at Sheffield and originally used to power the Ravenglass and Eskdale Railway locomotive ‘River Irt’

It was purchased as non-working boiler because of very bad corrosion in the firebox. In order for it to fit the boat it had to be shortened, a new dome fitted, the firebox was patched on one side, and modified to fit a new side-firing fire-hole, removal of all corroded areas – converting it from a locomotive to a launch boiler.

It is coal fired, built from 1/2" (12,7mm) riveted steel, the barrel being 1' 10" (560mm) diameter x 5' 8" (1470mm) long with 32 x 1 1/4" (31mm) internal diameter fire tubes.
Two Penberthy injectors feed the boiler with water directly from the Lake. Other accessories are a whistle, blower, bilge ejector and - very importantly –
a Windermere kettle which produces half a gallon of boiling water in about 20 seconds from cold. A white hemi-spherical porcelain hand basin with hot & cold running water (steam supplied) is fitted in the cabin.

The Hull
The hull is classed as a Saloon Launch, built to classic steam launch design in 1906 by Nathaniel Shepherd Boat and Yacht builder in Bowness. Length over all: 45' 11" (13.8m) with a beam of 8' (2.44m).

It is carvel built of teak planks on oak with elm timbers with a straight steam and a cruiser stern the aft saloon has a clerestory roof and the whole construction finished in clear yacht varnish. She was designed so that one person could steer, control the engine, fire the boiler, and tie up alongside – original one-man operation.

Steering is achieved via two wheels, one in the bow section and one adjacent to the engine. The drive to the rudder is by chain and solid rods to the stern to move the quadrant mounted on the rudder stock. The bow wheel allowed the owner to steer if he wished, but with a boatman to tend the engine and boiler.

The Propeller
The propeller is three-bladed, 27" (840mm) diameter x 40" (1m) pitch, left hand, and is driven via a 2" (50mm) diameter solid steel shaft. The original propeller on Swallow was borrowed to use as a pattern for casting in PB3 bronze at Vickers in Barrow. It was machined by Roger Mallinson and finished whilst working at sea.

Other boats of similar type
Shamrock is one of several similar boats built on Windermere boat yards over a number of years. None of the boats are identical, but all have their special features with Swallow being Shamrock's sister boat.

The other boats are currently not operational. Five of them were displayed at the Steamboat Museum until they were transferred in 2007 to the Lakeland Arts Trust who took all the boats out of the water for a much needed overhaul and this is still on going.

Five of the boats from the same era as Shamrock are:

Hull: 1896, Builder George Brockbank, Length: 50', Beam: 9' 2"
Engine: 1896, W. Sisson & Co. Ltd., Compound, 7½" + 11" x 7"
Boiler: 1971, Hunslet& Co., Locomotive type.

Hull: 1898, Builder T.W. Hayton, Length: 40', Beam: 7'
Engine: 1901, W. Sisson & Co. Ltd., Triple Expansion, 5" + 6¼" + 8" x 5½"
Boiler: 1984, H.A. McEwen (Boiler Repairs) Ltd., Locomotive type.

Hull: 1902, builder Nathaniel Shepherd, Length: 45' 6", Beam: 8'
Engine: 1901, W. Sisson & Co. Ltd., Compound, 5¼" + 8" x 5½"
Boiler: 1981, H.A. McEwen (Boiler Repairs) Ltd., Locomotive type.

Hull: 1906, builder Nathaniel Shepherd, Length: 45' 11", Beam: 8'
Engine: 2001, Roger Mallinson, Model: Roger Mallinson, Twin, 4" + 4" x 5"
Boiler: 1927, Yorkshire Engine Co. Ltd., Locomotive type.

Water Viper:
Built 1907 by Borwick& Son of Windermere, a saloon launch of carvel construction. Originally an Edwardian steam launch she has now been converted to Internal Combustion with the whole boiler section rebuilt to suit the new engine. She retains the funnel which is simply an extravagant exhaust pipe.

Hull: 1911, builder Nathaniel Shepherd, Length: 45' 6", Beam: 8'
Engine: 1911, W. Sisson & Co. Ltd., Triple Expansion, 4½" + 6" + 8" x 5½"
Boiler: 1990, H.A. McEwen (Boiler Repairs) Ltd., Locomotive type.

These boats all follow the same style of the times. A few other boats were built, some following the traditional wooden style, and some like Otto were made of steel. Other boats built at Shepherd's boat yard around the 1900's were Wasp and Waterlilly. Waterlilly is thought to be in poor condition.

The Future
After the damage caused by the floods of 2009 and 2015, Shamrock is now facing the future as one of the grand old ladies of Windermere. She retains a high ranking on the National Historic Ship Register and is now owned by the Shamrock Trust with Roger Mallinson as Chairman. The Trustees represent some of the finest expertise, relating to this type of craft, available in Europe today -and they are supported by the Friends of Shamrock, a willing band of volunteers who work with the Trust to keep SL Shamrock as she was in 1906: a much-loved steamer, offering the opportunity to glimpse life and cruising on Windermere as it was over a hundred years ago, including wonderful views, velvet upholstery and warm hospitality.