The Hooge Crater formed by the explosion.

July 19 1915, Hooge–The use of sappers and mines at Hill 60 earlier in the year had impressed many British commanders, even if the resulting gains were small and temporary. It was decided that another attempt would be made, this time to secure the (now-ruined) chateau at Hooge. A company of miners, brought in in June from England and Wales with no military experience, was placed under the command of a Lt. Geoffrey Cassels. Initial attempts were disastrous; the men did not handle being under enemy fire well, and the sandy soil they were supposed to be digging through was completely sodden and constantly oozing, flooding their tunnels. Attempts to pump out the water and, in a last ditch measure, shore up the tunnels with the kilts of dead Scotsmen, failed. A second attempt, dug deeper into clay, fared much better.

As this new tunnel was being excavated, Cassels’ observations of the German lines found that the Germans were not fortifying the chateau, but had instead constructed two new concrete redoubts nearby. Cassels then decided to have the tunnel branch into two sections, one for each redoubt. However, a few days later, it became apparent that the left tunnel was heading the wrong way and would miss the objective. With limited time left until the planned attack, Cassels improvised, proposing to just detonate one massive charge under the right redoubt, hoping to blow both up with one explosion. In order to do this, he needed a more powerful explosive than gunpowder, and requested 3500 pounds of ammonal. Headquarters had no idea what ammonal was, and was informed by the Medical Corps that “Ammonol is a compound drug extensively used in America as a sensual sedative in cases of abnormal sexual excitement.” This confusion added to the delay, and the ammonal explosive did not arrive until the day before the planned attack (and in full view of the Germans). They hurriedly began to place the explosive, which was ready, twenty feet under the Germans, by 2PM on July 19th.

The mine was set to be detonated at 7PM. A few minutes before, a shell hit, breaking the electrical leads from Cassels to the explosives. These were swiftly repaired, and soon it was 7PM. Cassels’ superior, Major Cowan, recalled of his vantage point a kilometer from the line:

A shell arrived near the work, and for two centuries my hair stood on end. But in eight actual seconds there was a cloud of smoke and dirt five hundred feet high, and an explosion and a real shake, even under our very feet. Then Hell was let loose and for twenty minutes every gun we had made a curtain of fire just beyond our objective.

The explosion was larger than Cassels had anticipated. In fact, ten to twelve British soldiers, who had inched a bit too far forward in anticipation of the attack, were buried alive. The rest of the attackers, however, were able to pour around the newly-formed 120 foot wide crater, capturing nearby trenches and still-shocked Germans. However, the Germans still had artillery superiority in the sector, and prevented the British from progressing much further. They now had to defend an awkward position, skirting a crater and with their lines uncomfortably close to the Germans’ in many places.

Today in 1914: Austrian Ministerial Council Officially Approves Demarche To Serbia



Sources include: Lyn Macdonald, 1915; Winston Groom, A Storm in Flanders.