This search is for the remains of the huge Zeppelin airship L-19 of the Naval Airship Division of the Imperial German Navy, lost in World War One and the only airship ever to bomb and sink a British ship at sea.
L-19 was one of nine Zeppelins despatched just before noon on 1 February, 1916 from Germany to bomb Liverpool. Kapitanleutnant Loewe was in command, with Leutnant Schirlitz as his executive officer. They rode in the foremost gondola under the 536ft long hull, packed with 1.13 million cu ft of hydrogen in 16 separate gasbags.
Other cars slung under the ship housed four 240hp petrol engines. Their propellers could push the airship along at 60mph. Altogether 16 men were charged with delivering 5000lb of bombs.
The nine raiders lost sight of each other as darkness fell and seemed unaware that a strong southerly wind was pushing them far from Liverpool. L-19 finally crossed the coast at Sheringham, Norfolk at 7.20pm. Loewe, completely lost, is believed to have bombed Burton-on-Trent and possibly Birmingham.
He was heard by British radio stations calling for bearings which put him somewhere near King's Lynn.
At about this time he found the 970 ton British collier Franz Fischer, anchored in the mouth of the Thames estuary. One of the 224ft collier's three survivors saw a bomb fall from the Zeppelin, which was stationary above the ship. It entered the Franz Fischer's funnel, the explosion blew out her bottom and she sank in less than a minute (if you want to dive her she is upright with her coal all around her, 6m proud in 23m, at 51 37.02N; 01 40.28E).
The next we know of L-19 is that her captain reported: "Radio equipment at times out of order. Three engines out of order. Approximate position Borkum Island." Sentries in neutral Holland put him further south over Dutch territory and fired at him with everything they had until he disappeared out to sea.

A Grimsby steam-trawler skipper, William Martin, said that before daybreak on 2 February he saw lights flashing in the distance. "I went towards the lights and discovered a huge mass of wreckage on the water," he told a Times correspondent. "I stood by and at daybreak found the wreckage was that of a large German airship bearing the identification mark L-19. The cabins were under water and so was a large part of the envelope, but a large portion was still above.
"On a raised platform on top of the envelope were seven or eight members of the crew, who hailed us in broken English saying: "Save us, save us! We will give you plenty of money'. An officer offered gold, but as he did so, 20 crew appeared."
The skipper of the unarmed trawler felt it would be unwise to take the Zeppelin's men aboard, as they outnumbered his own crew, so he went off and reported the incident to a British naval vessel. As he sailed away the Germans were shouting "Gott strafe England!" but a gale then got up and the airship probably foundered.
This extraordinary tale gives little idea of the exact position of the Zeppelin, but a further amazing twist does tell us where Kapitan Loewe thought he was sinking. A bottle with a note in it was washed ashore six months later in Sweden.
The message read: "With 15 men on the top platform and backbone girder of the L-19, floating without gondolas in approximately 3¡ east longitude, I am attempting to send a last report. Engine trouble three times repeated, a light headwind on the return journey delayed our return and, in the mist, carried us over Holland where I was received with heavy rifle fire; the ship became heavy and simultaneously three engines failed. February 2, 1916, towards 1pm will apparently be our last hour. Loewe."

Deadly dirigible: In February 1916 nine Zeppelins were sent from Germany to bomb Liverpool

With a name like that, you aren't going to have any trouble in Scottish diving circles! One splendid book is made for you - Scotland's Historic Shipwrecks by Colin Martin (published by Batsford in 1998). Colin Martin is one of the pioneers of underwater archaeology in Scotland (and the rest of Britain) and at present is working on the Duart Point wreck in the Sound of Mull, which is unique among protected wrecks in that visiting divers can be taken on a tour of the site. You can contact him at the University of St Andrews.

Ardeola puzzle
Can you help? We were diving in Plymouth Sound and found a lead nameplate, approximately 3in by 3in. It says "SS ARDEOLA", beneath it "1 1/8 LUGLEES"and beneath that "7 LENGTAS". It could be from a valve, as a hole in the top of the plate looks as though it was once wired on to something.

I can help a bit. A British steamer called Ardeola was built in 1888 by Caledon Steamship Builders, and owned by a firm called Yeoward Brothers. She was 1204 tons and measured 260ft, with a beam of 34ft and a draught of 15ft. Her triple-expansion engines produced 234hp. She was sunk in December 1903 in the Bay of Biscay in a collision while heading for Liverpool from Las Palmas with a cargo of fruit.
Perhaps someone else can help with the funny words.

Anchor on the Salsette - but what has been removed from its interior over the years?

What divers found on the Salsette
When you named the Salsette in Lyme Bay as Number 1 in the Diver guide to the 100 Best Wreck Dives in Britain, you said divers had made splendid finds in its interior. What exactly have they found?

John Westlake

We won't count the portholes raised - there were more than 300 on each side of the 5842 ton P&O luxury liner, each with its own brass drip tray. The bench ends of the deck seats were also brass, as were the fans, each in its own brass cage, and the companionway lamps, like everything else carrying the P&O monogram. The steering wheel has been raised - solid brass, of course - and hundreds of pieces of P&O crockery have been found by divers.
Most prized to some will be the gold watchchains and fob watches found by divers dribbling the silt through their fingers on the floors of the cabins. The chains are perfectly hallmarked on each link, though the workings of the watches have crumbled to black rust.
The luggage of the 31 passengers has yet to be found. One named bell, not large, has been brought up. But the most prized finds, by many Salsette divers, are china "potties" marked PO!

Terminal Hartburn
Can you give me the position of the 2367-ton British steamer Hartburn, sunk after hitting a mine laid by UC-62 on 15 October, 1917? It was travelling from Manchester to St Helens with a cargo of hay and trucks.

Jeannie Engela

Yes, the wreck at 50 30.74N, 02 06.42W in 39m is believed to be the Hartburn.

Chest challenge
Do you know what was found in the seaman's chest on the lower deck below the fo'c's'le of the Gibel Hamam wreck in Lyme Bay?

No, I don't, and I don't know a man who does. Chris Burton is one of the owners and is hoping for help with his research. The Gibel Hamam was a 647 ton British steamship, built in 1895 as the Bamburgh,180ft long with a beam of 29ft. She was torpedoed by UB-103 on 14 September, 1918 on route from Swansea to France with a cargo of coal. Only one of the 22 crewmen survived.
This is such an amazing question that someone must have the answer that will stop us all worrying about it!

Rosehill marks
It is many years since I dived the Rosehill in Whitesand Bay, Cornwall. Can you please supply GPS marks for that site?

Niall Deeha

The Rosehill, a 2788-ton steamer which was torpedoed on 23 September, 1917 by UB-40, lies at 50 19.67N, 04 18.42W.

Here's one for you...
Can anyone provide details of a shipwreck which scattered 4.7in brass shellcases (unfired and mostly dated 1941) over a wide area less than a mile off the cliffs of Seaford Head, Sussex. Many divers have come across them; there was talk of the loss of an ammunition barge in WW2, but no one seems able to put details or an exact date to the loss.