IT was an unfortunate day for union leader David Kirkwood to have chosen to visit Edinburgh. Used to turbulent times at the heart of bitter industrial disputes, even Kirkwood seems to have been shaken up by his experiences on one April wartime night in the city.
In his autobiography, My Life in Revolt, the engineering union activist writes: "Suddenly a terrifying explosion occurred. Windows rattled, the ground quivered, pictures swung. We all gasped. I ran to the window and saw Vesuvius in eruption . . .
"I opened the window. A great flash greeted me from the Castle and then, above the roaring, I heard the most dreadful screeching and shouting. The inmates in the Morningside Asylum had started pandemonium."
Kirkwood would be one of the lucky ones that night - there were others living close to the Castle who would suffer far more than a disturbed evening.
Aerial bomb attacks - particular on Kirkwood's native Clydeside - became a fairly regular occurrence during the Second World War.
But what is less well-known is that more than 1260 civilians died - and more than 3000 were injured - in aerial attacks on Britain during the First World War. As a BBC documentary, to be broadcast on Friday reveals, England had been badly hit during 1915 and 1916. But until 1917, these attacks were not launched by fighter planes - airborne technology was still too primitive.
Instead, the sight that loomed over Britain's cities and coasts - and over Edinburgh that fateful night of April 2 1916 - was that of an airship.
While some attempts had been put in place to protect the public in England, in Edinburgh there wasn't even a blackout, and the city was totally unprepared for what was about to be unleashed. Historian Sandy Mullay, author of the Edinburgh Encyclopedia and the Illustrated History of Edinburgh Suburbs, says: "In England the local authorities would lower the gas pressure - and that would alert the public but there is no record of that happening in Edinburgh."
And April 2, 1916, was a bright moonlight night, perfect conditions for navigating a Zeppelin. Jonathan Ferguson, assistant curator of military history at Edinburgh's National War Museum, explains: "They were a very primitive method of ordinance. They were pretty subject to weather conditions, like wind and fog and they navigated using ground features."
Sandy adds: "The individual bombs were dropped by hand. They were about the size of a sack of flour."
Even with the perfect weather conditions, the raid did not go exactly to plan for the two German navy airships heading for the city. Jonathan says: "There were supposed to meet up with two other airships but one turned back because of navigation problems." The other reached Britain, but appears to have got lost and released its bomb load over fields in Blyth in Northumberland.
So it was just two airships which reached the Firth of Forth in the early evening. But two was quite enough to cause carnage.
Their targets were not civilian - they were aiming for the docks at Rosyth and the fleet moored in the Forth.
Sandy believes the airships were repelled by the ships' defences, and it was only then they turned inland to the city itself. They were carrying 27 high explosive and 14 incendiary devices and their ' hunt for new targets was helped by an early hit - a bomb fell on a bonded warehouse at Leith and lit up the whole city. That bomb alone caused 44,000 of damage.
Several bombs fell along the shore at Leith, one hitting St Thomas's Parish Manse in Sheriff Brae and another falling on a railway siding at Bonnington, where a child was killed in its crib. An empty patch of land at Bellevue Terrace was hit, smashing windows in the surrounding streets.
One of the airships then appeared to aim for the Castle. A bomb hit the road by the Mound and another ploughed through the home of Dr John McLaren at 39 Lauriston Place, although no-one there was injured. Then one hit the Castle rock itself, sending splinters of stone tumbling down to smash windows in Castle Terrace. A plaque, high up on the rock, now commemorates the spot. As the Zeppelin wobbled in the air overhead, another of its deadly load struck the Grassmarket in front of the White Hart Hotel. Four people were injured, one later died. "Unfortunately people had rushed out to see it," says Sandy. The County Hotel on Lothian Road was also hit, as was George Watson's College where the west wing classroom windows were smashed - which at least brought pleasure to some. "On my road into school this morning," one pupil recorded the day after, "I met several joyous persons who informed me that the Easter holidays had begun - compulsorily . . . there were some compensating features even about an air raid."
Not for those standing on Marshall Street when the attack happened. There, a group had taken refuge in the entrance to a tenement when a bomb hit the pavement just outside. Six died and seven were injured. And at a tenement on St Leonard's Hill a child was killed and two people injured.
There were also miraculous escapes - a bomb hit a tenement on Marchmont Crescent and went through the ceilings and floors of three storeys without injuring anyone. And a five-flat tenement on Causewayside was wrecked but again with no human cost.
There were only two attempts to ward off the attacks. Jonathan says: "For the only time in its history the One o'Clock Gun was fired [in action] but they were only blank shots as they are now." And as the Zeppelins moved out towards East Lothian, an Avro 504, piloted by Flight Lieutenant GA Cox, took off from East Fortune airfield. Unfortunately he did not manage to make contact with the Zeppelin. "Then he crash-landed when he returned and was quite badly hurt," says Jonathan.
With that, Edinburgh's first and only air attack of the First World War was over. The repercussions, however, would last much longer. An official German report spoke of a bombardment of "the northern part of Edinburgh and Leith, with docks on the Firth of Forth". The British dismissed this as: "A statement of the usual inaccurate and bombastic type".
However, the authorities were rattled - particularly after furious letters began appearing in the newspapers, including the Edinburgh Evening News, about why the city was so badly prepared. Within days, discussions were beginning about systems to automatically dim the lights and the raid led directly to the setting up of three airfields, Gilmerton, Colinton and Turnhouse.
There was one other lasting consequence - when just over 20 years later war again began to brew in Europe, the attacks and the lack of preparation to combat them was one factor which led to the galvanisation of the country's home front. From air raid shelters and evacuations to camouflage on the top of buses and a strictly enforced blackout, when the Second World War broke out, the city, and the rest of Britain, had braced itself - a fact which could well have saved many lives. "In 1916 there was no preparation," says Sandy. "By the Second World War it was the exact opposite, if anything, they were over-prepared.
• Timewatch's The First Blitz is on BBC2 on Friday at 9pm
HIGH-FLYING DESIGN THAT CRASHED TO EARTH
THE world's first rigid airship was flown in 1900, carrying five passengers, near Lake Constance in Germany. It had been built by Zeppelin Co, owned by Count Ferdinand Graf von Zeppelin.
By 1910 Zeppelins were in commercial use, carrying civilian passengers. At the outbreak of the First World War in 1914, when Germany had ten Zeppelins, pilots were trained and airships designed and modified for war use. By 1918, Germany had 67.
The first Zeppelin raid on Britain took place in May 1915, and more followed into 1916, until improvements in planes' speed and range saw Zeppelins become obsolete as war weapons.
Zeppelins survived the war to continue as passenger-carriers but the Hindenburg disaster of 1937, in which 35 passengers were killed, effectively ended airships' use as a form of transport.