Instead, alighting on the stern, they found a single gun mounting and the deck area littered with boxes of four-inch shells. Then they found the hull regularly punctuated by portholes, and the area littered with
toilets and sinks. This was no tanker.
In fact, the divers had discovered the wreck of the St Briac, a 316ft-long former cross-Channel ferry which had been hired by the Royal Navy in 1941 as a Fleet Air Arm target-towing vessel, attached to HMS Condor at Arbroath. On the morning of 12 March 1942 she sailed out of Dundee. Just before 1500 hours, its master, Captain Rupert Lubbock RN, sent a distress signal to say that the vessel had broken down in a south-easterly gale and was drifting towards a British minefield, 20 miles off Arbroath.
There was a sudden explosion and a plume of water as the St Briac struck one of the mines. As the Arbroath and Montrose lifeboats, plus four armed trawlers and a French rescue tug, all made full speed ahead towards the ship's last reported position, the St Briac sank, with 47 hands lost.
As the millions of dead from two world wars are remembered this morning – the 11th hour of the 11th day of the 11th month – the St Briac is not a name you'll hear in the same breath as some of the major maritime disasters, such as the Hood, the Royal Oak, the Lancastria or the Rawalpindi, horrifying incidents in which hundreds, sometimes thousands, of people lost their lives. But the loss of the St Briac symbolises the kind of unsung, everyday sacrifice which seamen in the Royal and Merchant Navies were making during the routine business of protecting Britain and training those doing the protecting. The civilian status of merchant seamen was no safeguard, as any veteran who was stalked by U-boats on the hazardous Atlantic convoys, or ran the gauntlet of Arctic weather and German bombers on the Murmansk run, will tell you.
The surviving crew escaped into the St Briac's lifeboats, one of which was picked up by the tug Empire Larch. However, another capsized and was eventually washed ashore at Collieston, north of Aberdeen, with 13 of its 17 occupants drowned. Of the total 47 dead, some were essentially civilian seamen operating on a vessel hired by the Royal Navy – six of those killed were crewmen with Southern Railways, who ran the vessel when it was a cross-Channel ferry before the war – others were members of the Royal Naval Reserve or of the Royal Naval Patrol Service.
The vessel, built in 1924 by Denny's of Dumbarton, had an adventurous early war career, having taken part, along with its sister ship Dinard, in the Dunkirk evacuations of June 1940. Her Royal Navy captain, Rupert Lubbock, survived the sinking but not the war – he was killed on active service little more than a year later, a day after his 57th birthday.
Maritime historian and former sports diver Bob Baird, whose research into the St Briac sinking is included in his forthcoming book Shipwrecks of the Forth and Tay, says that the casualties came from as far apart as Dundee, the Channel Islands and the Western Isles. It is one of several notable wrecks discovered this year by sports divers using improved diving technology such as rebreathers and the Trimix blend of oxygen, helium and nitrogen, which allows them to stay underwater for longer periods.
"These wrecks were not unknown, but their identities weren't known," says Baird, 67. "Fishermen have known about them all their lives, but wouldn't know what they were. They have nicknames for all the wrecks. The nickname for the St Briac, for example, was 'the Hospital Ship'. It never was a hospital ship and even the fishermen can't tell you why they call it that."
Wrecks such as the St Briac are not officially war graves, but may be regarded as such unofficially – although by this time there are unlikely to be any identifiable human remains left in the wreckage. However, the visiting divers had mixed feelings about the St Briac. Jeremy Cameron, 39, a petroleum engineer living in Aberdeen and a member of Deeside sub-aqua club says: "Going down on the deck was a fantastic feeling, knowing that you were the first one to have dived it.
"Then you thought how it got there in the first place and that 47 people were lost with it. There are probably people around who'd be really glad to know that the wreck, the last resting place for (one of] their relatives, has finally been found."
Cameron and his fellow sports divers sailed from Eyemouth, on a dive boat run by Marine Quest. Having marked the wreck they thought was an oil tanker, they investigated it for the first time. "Visibility was really good for 25m, so as you went down you could see the wreck below," recalls Cameron. "It's well broken up in places, certainly in the midship section, but you can see rows of portholes, lots of sinks, and toilets, so we knew straight away this wasn't a cargo ship, but perhaps some sort of ferry or liner. Also scattered around were lots of plates and cups, some still stacked in piles."
Still unaware of the vessel's name, the divers started searching for the ship's bell: "We don't take anything from these wrecks, apart from something to identify the wreck with. So I was very lucky to see the bell lying on the seabed, just beneath the bow." On the surface, they scraped off the barnacles to reveal the name St Briac, and Bob Baird's research did the rest.
The find has been reported to the Receiver of Wrecks, who will trace the present owner, whether that is an insurance company or the successors of the vessel's original owners, the Southern Railways Company. If the bell remains unclaimed, Cameron hopes it may be displayed in Eyemouth.
The identification of the St Briac, as well as other wrecks off the Forth and Tay estuaries in recent months, has caused much excitement in the diving world, says Baird. "We found the First World War German submarine U12 in off the Forth; that had been missing for 90-odd years. Not only that, but we've even made contact with a relative of one of the Germans who was lost, who turns out to be a very senior diplomat."
But such discoveries have emotional import far behind the thrill felt by the divers. One such find that Baird was proud to have been involved in was the discovery of HMS Exmouth, a destroyer torpedoed in the Moray Firth in 1940.
"The entire crew (189 hands] was lost and it remained unfound for over 60 years until we found it in, I think, 2000 (actually July 2001]. Contact was made with some of the relatives and eventually about 160 of them went to a memorial service in Wick. That was an unbelievably emotional weekend.
"I'd like to think that with the discovery of the St Briac, some relatives of the 47 dead might get to hear about it and perhaps gain the same sense of closure that the Exmouth relatives did."
Shipwrecks of the Forth and Tay is published by Whittles Publishing, Dunbeath, at the end of this month.
BACKGROUND: THE MERCHANT NAVY
REMEMBRANCE wreaths for merchant seamen who died in both World Wars are placed at The Cenotaph and other war memorials next to those of the armed forces.
In fact, the very term "Merchant Navy" was granted to the service in honour of its sacrifices made during the First World War. Since 2000, Merchant Navy Day has been marked annually on 3 September.
During the First World War, the advent of "unrestricted warfare" meant that merchant vessels were as much at risk of attack from enemy ships and aircraft as were warships. Almost eight million tons of merchant shipping, and 14,661 merchant seamen, were lost to U-boat attack alone during the First World War, and it was in recognition of these losses that King George V granted the title "Merchant Navy" to what was previously known as the Merchant Service.
In the Second World War, U-boats sank nearly 14.7 million tons of Allied shipping – 2,828 ships, with 30,000 merchant seamen perishing on convoys.
According to Commonwealth War Graves Commission figures, the total of merchant shipping lost during the first World War was 3,305 – and more than 17,000 lives – while during the Second World War, a total of 4,786 merchant ships and nearly 32,000 merchant seaman were recorded lost.
However, the actual figures for both wars are probably considerably greater as, unlike casualty statistics for the armed forces, merchant seamen who died subsequent to being removed to hospital were not recorded as losses.