But British Hold Their Lines.

Both Sides Planning Strategy for 1916.

Special to The Great War Project

(17-20 December) On December 19th precisely a century ago, the Germans use phosgene gas on the battlefield for the first time.

Phosgene is ten times more lethal than the chlorine gas used up until now. Its target: The British forces on the Ypres Salient in Belgium.

French soldiers wear primitive gas masks on the Western Front.

French soldiers wear primitive gas masks on the Western Front.

Phosgene gas2

Allied machine-gunners with gas protection gear, Western Front, date and place uncertain.

“Their aim,” writes historian Martin Gilbert, “was to cause panic and a mass retreat. But the British troops, who had been surprised by the new [gas] weapon in April, were now well trained in gas drill and well equipped with gas helmets.”

“A thousand soldiers were gassed, and 120 killed,” reports Gilbert. “The wind was strong on that day, blowing the gas cloud southward across the British lines and far to the rear; because of a curve in the line, some of the gas was blown along the German trenches.”

“The hoped-for British panic did not take place, and the line held.”

Phosgene is certainly a weapon of terror. “The scene must have been as near to hell as this earth can show,” writes war historian John Keegan. But neither phosgene nor its predecessors — chlorine and mustard gas — play a decisive role on the battlefield.

“Its intrinsic limitations as a weapon,” observes Keegan, “dependent as it was on wind direction, and the rapid development of effective respirators, ensured however that it would never prove decisive, as it might have done if large reserves had been at hand to exploit the initial surprise achieved by the Germans.”

At the same time, both sides in the war are looking ahead past the new year to determine how they will continue to fight until victory.

On December 19th a century ago, the general in command of the British army in France, Sir John French, is replaced by Sir Douglas Haig. Haig is a rigid strategic thinker with a dedication to mass offensives in the face of withering machine-gun fire. His receiving command on the Western Front is “an ominous day for millions,” writes historian Gilbert.

At the same time, the British and their French allies are making plans for waging the war in the coming year, 1916. The talks among the Allies take place at Chantilly, in northern France.

Allied military leaders meeting at the Chantilly headquarter of Gen. Joseph Joffre, left, supreme French commander, December 1915.

Allied military leaders meeting at the Chantilly headquarter of Gen. Joseph Joffre, left, supreme French commander, December 1915.

“Plans were also laid at Chantilly for an Allied victory on the Western Front in 1916,” reports Gilbert, “when [French commander-in-chief] Joseph Joffre obtained British agreement for a joint and simultaneous Anglo-French offensive in the summer of 1916.”

It will take place north and south of the river Somme.

The Germans too are busy planning their strategy for the new year. The German commander-in-chief Erich von Falkenhayn is preparing a letter to the German Kaiser, outlining his strategy.

“Germany’s object,” he insists, “must be to dishearten Britain on whose industrial and maritime power the Alliance rested.”

The way to do this, Falkenhayn insists, is to resume the unrestricted U-boat campaign of submarine warfare.

But observes historian Keegan, Falkenhayn “rightly surmised that this call would be refused.” His fallback position: Mount an offensive to destroy Britain’s continental partners, especially Russia, weakened on the battlefield and facing unrest at home.

“Russia tied up German troops which could be better used elsewhere,” Falkenhayn writes.”Even if we cannot perhaps expect a revolution in the grand style, we are entitled to believe that Russia’s internal troubles will compel her to give in within a relatively short period.”

That leaves France. “Germany and her allies could not hold out indefinitely,” Falkenhayn writes, so the attack must be made soon against France.

“The strain on France,” he writes, “has reached breaking point…

…If we succeed in opening the eyes of her people to face up to the fact that in a military sense they have nothing more to hope for, that breaking point would be reached and England’s best sword knocked out of her hand.”

Gilbert writes: The operational solution to this analysis “was for a limited offensive at a vital point that would compel the French to throw in every man they have.”

“If they do so,” Falkenhayn concludes, “the forces of France will bleed to death.”

The “vital point” that Falkenhayn sets his sights on?

The northern French town of Verdun.