The Armament of Melbournes' Forts

The Crows Nest position
It covered the blind spot to the Fort towards Point Lonsdale. It was built from 1886 and mounted 1 x 8 In B.L. of 12 Tons on H.P. mounting and 1 x 6 Pr Nordenfelt Q.F. gun on a balanced pillar mounting* for close defence. Both guns were made in 1887 and so of course that is the earliest year in which they could have been emplaced. Both were there as of 1901.

Fort Queenscliff
1885 -3 x 9 In 12 Ton Armstrong Original
Construction R.M.L.'s(on Iron Traversing Platforms)
4 x 80 Pr 81 Cwt (Victorian Order,made by R.G.F.) R.M.L.'s(on Wood Traversing
Platforms)
(+ 2 x 40 Pr Armstrong 'Rifled Breech Loaders' on heavy field mountings)
1887: As above, including;
1 x 6 In B.L. of 5 Tons Armstrong (on H.P. mounting)
1 x 8 In B.L. of 12 Tons Armstrong (on H.P. mounting)
(+ 2 x 6 Pr Armstrong 'Rifled Breech Loaders' - on field mountings?, and 2 x 10 Barrelled 0.45 cal Nordenfelt mechanical machine guns)
- One variation is that one of the 80 Pr R.M.L.'s has been placed on an H.P.
mounting.
1889: 3 x 80 Pr R.M.L.'s of type above(2 on Wood Traversing Platforms, and 1 on
H.P. mounting)
2 x 6 In B.L. of 5 Tons Armstrong (on H.P. mounting)
1 x 6 In B.L. of 4 Tons Armstrong (on shielded Central Pivot Vavasseur naval
type mounting)
2 x 9.2 In B.L. 20 Tons Armstrong (1 on H.P. mounting, 1 on Central Pivot
Barbette mounting)
1 x 6 Pr Nordenfelt Q.F.
1901: 1 x 80 Pr R.M.L. still on H.P. mounting)
3 x 6 In B.L. of 5 Tons Armstrong(2 on H.P mountings, and 1 on Central Pivot Barbette
mounting)2 x 6 In B.L. of 4 Tons(on shielded Central Pivot Vavasseur naval type mounting)
2 x 9.2 In B.L. 20 Tons Armstrong(1 on H.P. mounting, 1 on Central Pivot Barbette
mounting) There were also 4x 14 Pr (3” cal) Nordenfelt Q.F. guns, apparently not 'fully' mounted, as a saluting battery, plus a 4.7 In Q.F. gun on site. This last one may have been in reserve, i.e. not emplaced. Lastly there were 1 x 2 Barrelled 1 In cal and 4 x 5 Barrelled 0.45 cal Nordenfelt machine guns available

Swan Island
1882: 2 x 9 In R.M.L.'s
1 x 80 Pr R.M.L.
1885: 5 x 80 Pr R.M.L.'s
1 x 6 In B.L. of 4 Tons was added during the year
1887: 1 x 9 In R.M.L.
4 x 80 Pr R.M.L.'s
1 x 6 In B.L. of 4 Tons
(+ positions for 2 x 'Nordenfelt machine guns' - mounted/type?)
Sometime later: 2 x 6 Pr Nordenfelt Q.F guns on Balanced Pillar mountings added
1889: 2 x 5 In B.L. of 3 Tons on H.P. mountings added
June 1890: 1 x 9 In R.M.L.
3 x 5 In B.L. of 3 Tons on H.P. mountings
1 x 80 Pr R.M.L.
2 x 6 pr Nordenfelt Q.F.
2 x 'Nordenfelt machine guns'
Later 1890: total 4 x 5 In B.L. of 3 Tons on H.P. mountings
(+ the othe gun types as for June 1890)
1901: 8 x 5 In B.L. of 3 Tons on H.P. mountings
2 x 6 Pr Nordenfelt Q.F. guns on balanced Pillar mountings
(+ 2 x 5 Barrelled 0.45 cal Nordenfelt mechanical machine guns)

Note: There were a total of 6 x 9 In of 12 Tons R.M.L.'s Armstrong Original construction in the colony. They were shifted around to different places at different times. This was the only model of the gun in Victoria. NSW and SA had different models/marks but they all stayed in their state of 'origin' before and after Federation. They were only ever mounted on Iron Dwarf Tarversing Platforms wherever they were. There were a total of 25 of the 80 Pr R.M.L.'s of the 'Victorian' type in Victoria. Like the 9” they were used in different places (handy to fill in gaps). Unless otherwise stated, they were mounted on Wood Traversing Platforms just like the older 68 Pr Smooth Bore Muzzle Loaders. (I'll get to other mountings for this gun as applicable to other batteries/forts).

There were both 2 Ton and 3 Ton versions of the 5 In B.L. guns.

The 6 In B.L. of 4 Tons Armstrong was a naval service weapon which found its way on land - mounting always is as described for Fort Queenscliff.

*The Ballanced Pillar mountings were one of those things which came about, it would seem, simply because those late Victorian engineers could do it! Just as the same types of 'big' guns (e.g. 9.2 In of 20 Tons) could be placed on a H.P. mounting as well as a Barbette mounting (which didn't require the same complexity), lighter guns had the Ballanced Pillar in addition to ordinary (barbette) mountings. I've seen diagrams for both 6 Pr and 4.7 In guns on the 'BP'. The normal pedestal for the gun sits on a steel pillar or cyclinder which allows it to be raised or lowered behind a parapet or into a pit. This can be done mechanically or hydraullically. The guns stays 'up' throughout any action, unlike the H.P.

Westernport Bay
There was nothing in the way of fixed defences.

The VMF disposed of the following field guns:

1885: 12 x 12 1/2 Pdr B.L.
6 x 12 Pdr
6 x 40 Pdr R.B.L.
1896: 19 x 12 Pdr B.L.
6 x 12 Pdr R.B.L.
6 x 6 Pdr R.B.L.
6 x 40 Pdr R.B.L.
1901: 18 x 12 1/2 Pdr B.L.
6 x 40 Pdr R.B.L.
6 x 6 Pdr R.B.L.