Avernus (NSW Colony)

The early maritime defence of the colony of New South Wales was, for the most part, provided by Royal Navy ships based in Sydney, and small detachments of Royal Marines and infantry troops. The relative isolation of the Australian colonies, however, far removed from events in Europe, meant that the actual provisions for the defence of the colonies was far from adequate. This fact was brought into stark relief by the unexpected and unannounced arrival in Sydney Harbour of four men-o-war of the United States Navy, under the command of Commodore Charles Wilkes, in the early hours of 3 December 1838. While the American squadron was on a peaceful, round-the-world journey, the implications of their unmolested arrival in the harbour were clear. As Wilkes himself commented; “Had war existed, we might, after firing the shipping, and reducing the great part of the town to ashes, have effected a retreat before daybreak, in perfect safety.”

Between 1855 and 1859 the gunboat SS Spitfire provided a local visible attempt to protect the harbour, but on 1 March 1859, when HMS Iris became flagship of the Australia Station, a continuing presence of the Royal Navy in local waters was guaranteed.

For the next 52 years a further twelve flagships would head the Royal Navy squadron, with occasional visits from special task groups such as the Flying Squadron in 1869 and the Detached Squadron in 1881. Usually the permanent force would comprise the flagship, and between six and twelve other men-o-war, comprising all types.

Residents in the growing Sydney region, however, desired a local effort to protect their homes and families. This attitude spread to the other colonies, assisted by the emerging Russian threat of the 1879s and 1880s. This threat was never of any real consequence in Australia but frequent reports in the press warning of foreign warships off the eastern Australian coast led, in 1877, to the Government of the colony of New South Wales ordering the construction of two ‘outrigger’ torpedo boats to conform closely to the design of 2nd class torpedo boats constructed by the British firm, JI Thornycroft & Co.

Tenders for the two boats closed on 17 January 1878, with £8784 allotted for construction. The vessels were to be named; Acheron, taken from a river in the Epirus region of northwest Greece and a name of one of the rivers of the underworld in Greek mythology; and Avernus, the name of a lake within a volcanic crater, also named Avernus, in the Campania region of Italy west of Naples. Avernus was believed to be the entrance to the underworld in Roman mythology and is portrayed as such in Virgil’s Aeneid.

Avernus in Sydney Harbour, circa 1890.

The Atlas Engineering Company at Pyrmont was chosen as the successful tenderer for the two torpedo boats with completion scheduled for March 1879. With the design modified locally by the renowned engineer and naval architect, Norman Selfe, construction of the two vessels was a remarkable achievement considering that this type of torpedo boat had only recently entered service with the Royal Navy. Acheron conducted her first trials on Sydney Harbour on 1 March 1879 achieving a speed of nearly 14 knots on a number of her runs and, by all accounts, handled well. During her second round of trials in April, Acheron covered a mile in just under 4 minutes and 13 seconds, making her fastest recorded vessel in Australia at the time.

The boats were divided into ten watertight compartments and could be steered from the stern or from a small sunken position forward of the funnel. From this position the helmsman also had the duty of launching the torpedos. They were based at Berry’s Bay and, when not employed in exercises, were often used for dispatch purposes.

The two ships were fitted with a variation of the standard torpedo spar. The spar was a wooden rod 62 feet (18.9 metres) in length, 45 feet (13.7 metres) of which protruded over the bow, with an explosive affixed to its tip. To make an attack the torpedo boat would have to make a stealthy approach on its target at low speed and usually in the dark in order to avoid detection. The spar would then be lowered into the water and swung out at right angle allowing the torpedo boat to turn parallel to her target. Once close enough the explosive could be fired at the target via a lanyard or detonated on contact. The torpedo boat’s parallel orientation meant that, in theory, it would speed away avoiding damage from its own weapon.

A diagram of the Spar Torpedo system, a variation of which was utilised by Avernus and Acheron.

The boats’ activities were confined to the waters of Sydney Harbour and were normally only active on weekends and public holidays. By April 1885 they were reported to be in a state of disrepair and required drydocking at Cockatoo Island. The following month the boats were modified in Morts Dock in Sydney to carry more modern Schwartzkopff 14-inch torpedoes launched from cradles mounted on both the port and starboard sides. There is no record of the vessels ever actually firing their torpedos. They both underwent further refits in May 1896.

On 1 March 1901, following Federation, Acheron and Avernus were integrated into the Commonwealth Naval Forces; however, less than a year later it was announced that the two boats were to be sold. They were sold at auction in November 1902.

Acheron was renamed Jenner and continued to serve as a quarantine boat on Sydney Harbour until 1914, and then as a coastal trader before her deteriorating hull led to her being scuttled off Barrenjoey Head. Avernus’ post-naval career was less auspicious. After reportedly operating briefly as a tug she was abandoned on the shores of Double Bay before being moved to Balmain in the early 1920s. Her fate thereafter is unclear.

Further reading

• Bach, John. The Australia Station: A History of the Royal Navy in the South West Pacific 1821-1913, University of New South Wales Press, Kensington NSW, 1986.
• Gillett, Ross. Australia’s First Warship - The Torpedo Boat Acheron, Naval Historical Society of Australia (navyhistory.org.au).
• Hunter, James W. ‘Last Line of Defence: A Brief History of the Torpedo Boats and Torpedo Boat Support Facilities of Colonial New South Wales’, The Great Circle, vol. 37, no. 2, 2015, pp. 54-75., www.jstor.org/stable/24583103.
• Nicholls, Bob. The Colonial Volunteers: The Defence Forces of the Australian Colonies 1836-1901, Allen & Unwin, Sydney, 1988.