THIS MONTHS TOUR TAKES US TO a nice little 252-ton wreck off the north coast of Pembrokeshire, easily located as it rests off the Upper Sledge, a reef just below the surface, and the nemesis of our wreck.
Having run across the Upper Sledge on 24 November, 1892, the Musgrave slid and rolled down the reef as it sank, coming to rest upside-down at a depth ranging from 23-28m. Its an ideal wreck for relatively inexperienced divers, because it is small enough for a quick tour without getting into decompression. At the same time, more experienced divers can enjoy poking their heads into holes to see what they can find beneath the hull.
When I dived the Musgrave, Celtic Diving had a buoy tied to the keel (1) below the base of the engine (2). This is a very basic two-cylinder compound unit, evidence of the age of the Musgrave and the origins of its engineering among the early generations of steamships from 1871.
The crankshaft is exposed, and from the aft end of the engine the propeller-shaft immediately disappears beneath the upturned keel (3), not that interesting as wreckage goes, but covered in marine life and a direct route to the stern.
Where the hull begins to curve for the stern, the propeller-shaft emerges again (4). At the end of the shaft, the blades of the propeller (5) are mostly broken off from when the Musgrave ran across the Upper Sledge.
From the propeller, the rudder (6) lies just downhill in a gully between the rocks. The interesting feature here is the curved tiller at the top of the rudder-shaft, evidence of the early design, where the rudder just attached at the stern of the wreck, rather than through the hull.
A little further downhill, the deepest part of the wreck is a small square hatch coaming (7) at 28m.
Heading back towards the engine at a more leisurely pace, sections of ribbed hull lie flat on the seabed (8), broken from the upturned keel. Peering under the edges of the hull, many lobsters have set up home.
A bit further out, among sparsely scattered beams and scraps of plating is a small winch (9).
Forward of the engine, a single boiler (10) rests slightly uphill from the wreck. The keel forward from the engine soon breaks against a wall of rock, where a section of mast also lies (11). The keel resumes a couple of metres shallower, twisted almost through a right angle, though still upside-down.
Between this forward section of keel
and the boiler is the helm (12), flat on the seabed and next to a flanged ring that may have been one end of a water tank.
Exposed ribs and rocks below hold the forward section of the keel (13) clear of the seabed, so it is easy to look below.
The keel eventually narrows and breaks (14) above another large rock. Just to the outside of this lies the spare propeller (15), consisting of four iron blades, with one disappearing beneath the hull.
Taking a line from the keel and continuing forward a few metres, the ribbed triangle of the upturned bow deck (16) rests flat on the seabed, and marks the last piece of wreckage on our tour.
From here it all depends on gas remaining, slack water remaining and how much deco divers want to accumulate. An easy ascent is to return to the line or release a delayed SMB and end the dive now.
For a longer dive, you could go round the wreck again, or follow the reef up to the Upper Sledge. If you do this, bear in mind that you will need to swim off the rock before the boat can come and pick you up.
It would also be a good idea to inform the skipper of your intentions, as he will then know to look in the right direction.

Thanks to Mark Dean, Bob Lymer and Jim Hopkinson

BUILT FOR RELIABILITY
THE MUSGRAVE, cargo steamer. Built 1871, SUNK 1892

IN THE EARLY HOURS OF 24 NOVEMBER, 1892, the little steamer Musgrave set out on her last voyage. She left Briton Ferry near Swansea while it was still dark and headed up the Pembrokeshire coast, holds crammed full of coal destined for the Irish port of Dundalk, writes Kendall McDonald.
The Musgrave really was small - 130ft long, 20ft in the beam and just 10ft deep. She had been built by Edward Linsey at Newcastle-on-Tyne in 1871. To fit the rest of her, she had one boiler, a single screw and a two-cylinder composite engine of 40hp.
She could never be described as speedy, but that suited her owners, Thomas Harries Brothers of Swansea, who said that they valued her for her reliability, not for speed.
Her captain, David Jones, shared his bosses opinion of his ship, as did his crew of eight, who had been with him and the Musgrave for years.
She plodded on through the morning and afternoon, but it didnt get any lighter. If anything the mist that had come up seemed to get thicker the more the wind increased from the South-east.
As it got darker, that wind became a force six, and the visibility was soon so bad that the Captain and Mate were setting their course by the compass. They saw no sign of St Davids Head.
This lack of a shore sighting of the great headland worried the Mate so much that he suggested to the Captain that they should swing to port to cross to the Irish coast.
Captain Jones rejected the idea as being premature. None of his lookouts had seen any sign of the rocks that towered out from the Head itself.
Nor had they seen any of the reefs which the chart festooned with wrecks around Bell Rock and the North Bishop islet.
In fact, they travelled past St Davids Head and were now amid the Sledges reefs, which had a fearsome reputation.
Minutes later, the Musgrave added to that reputation by harpooning herself on the most ill-famed of all the Sledges - a rock that was properly called in Welsh Llech Uchaf.
The rock was not yet showing above the surface, but the keel of the Musgrave was ripped out, together with a large section of her bottom, before the engine stopped running.
Then she rolled over and down the slope of the Upper Sledges into deeper water. Somehow all aboard got themselves ashore with only cuts and bruises, and found shelter in the little port of Porthgain, which is just a mile from the wreck site.
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