On New Year’s Day, 1915, a German torpedo sank a British battleship off the Dorset coast, sending hundreds of men to a watery grave.

Next day one lifeboat washed up on the beach and those on board, the bodies and the barely alive, were taken to a pub nearby.

The dead were placed in the beer cellar where the landlord’s dog, Lassie, began to lick the face of one sailor.

Half an hour later it was realised that the man was still alive.

The story of Lassie and the sailor from HMS Formidable reached Hollywood, inspiring the famous films of the collie that bears Lassie’s name.

Able Seaman John Cowan was given up for dead as rescuers instead concentrated on saving survivors washed ashore alive.

But the landlord’s collie dog refused to leave Cowan’s side as he lay motionless in the Pilot Boat Inn in Lyme Regis, where sailors from the sunken battleship had been taken.

She sat by his motionless body, and continued to lick and nuzzle him for half an hour.

Amazingly, the “drowned” sailor began to stir and rescuers rushed to his aid.

The crossbred collie – called Lassie – had saved his life. Some said that the dog had been trained to raise the alarm as the landlord Tommy Atkins’s wife was an epileptic, while others put it down to canine instinct.

Either way, it was a happy ending on a dark night for the Formidable and Britain’s navy. A total of 547 men perished when the pre-Dreadnought vessel became one of the first British battleships of the First World War to be sunk by an enemy submarine.

Cowan and the 200 men who survived were lucky to be alive at all.

The battleship was bringing up the rear of a line of warships from the Fifth Battle Squadron that was taking part in firing and steaming exercises off Portland. Many of the 747-strong crew had hoped to spend New Year’s Eve in the pubs of Portland but much to their disappointment were ordered to remain on exercise at sea overnight on December 31 and into the early hours of January 1.

No enemy U-boat activity had been reported in the Channel for a month but that was to change at about 2.20am that morning. German U-24, operating out of Flanders, had been tracking the squadron all day and picked its moment to send a torpedo straight into the Formidable’s second boiler, just abreast of the foremost funnel. The ship lost all steam and immediately keeled over 20 degrees to starboard.

The captain, Arthur Noel Loxley, ordered all watertight doors closed and the crew to be piped to collision quarters. Sailors remained completely calm as they launched lifeboats in the pitch black, while the sea grew rougher.

Two lifeboats were lowered but one violently capsized immediately and hurled its load of sailors overboard into the cold waters.

Meanwhile the submarine commander, Kapitanleutnant Rudolph Schneider, stayed in the area to confirm his kill.

Just to make sure the Formidable was finished he sent another torpedo whistling into the stricken warship from just 160 metres away, 45 minutes after the first strike.

This second torpedo hit the ship’s number one boiler, near the funnel on the port side, and rocked the ship back on to an even keel.

Captain Loxley gave the order to abandon ship and told the men remaining on board: “Lads, this is the last. All hands for themselves and may God bless you and guide you to safety.”

According to reports he then ‘walked to the forebridge, lit a final cigarette and with his faithful and beloved terrier Bruce by his side, waited for the inevitable to happen in true Royal Naval tradition.’ Captain Loxley had been given the Airedale/Irish terrier cross by his son Peter at the outbreak of war.

Three-year-old Bruce and the captain became ‘joined at the hip’ and looked after each other – even to the very end. As the Formidable went down, Bruce refused to leave his master’s side for the safety of a lifeboat.

Bruce’s body was subsequently washed ashore at Chesil Beach, and he is now buried at the nearby Abbotsbury Gardens, with an inscribed headstone marking his place of rest.

As the Formidable slipped below the waters of Lyme Bay, she left hundreds of men desperately trying to cling on to anything afloat in the tumultuous seas and pitch black.

By now strong winds had taken hold and survivors in the boats had trouble staying afloat as the waves threatened to capsize them.

Many men in the sea were engulfed by the waves.