�y��vlog

A 1,000ft tunnel was filled with 27 tonnes of ammonal explosive and the resulting explosion threw debris 4,000ft into the air.

The idea was to place a bomb made from gelignite and ammonal on the viewing platform at the top of the pillar, with a timer set to go off in the early hours of the morning when the street would be empty.

Ammonal women, the heaviest drinkers - 12 percent - were between 51 and 70 years old.

Some Blasting Explosives Ammonal: ammonium nitrate 80 to 90 per cent, aluminium 4 to 18 per cent, charcoal 2 to 6 per cent.

Their own work was done quickly lest the enemy should discover the secret of these borings beneath their lines before the ammonal with which they were packed was detonated on the morning of the battle.