THE BATTLE OF THE "GRAND COURONNÉ"
ALL along the frontier common to France and Germany by the Treaty signed after the Prussian victory of 1871 the French had erected, at a cost equivalent to at least three years of the national revenue, a chain of fortresses of the strongest sort.
Nothing surpassed them in the science of their time. There were, as we have seen on a former page, four great rings--those of Belfort, Epinal, Toul, and Verdun--each ring protecting vast supplies, and forming a great intrenched camp. Along the southern half of this line, which is mountainous, and coincides with the range of the Vosges, a string of forts linked up the system. Along the northern part, the line of the Upper Meuse, a further chain of forts linked up Toul with Verdun.
The invention of aircraft (which enables the exact fall of a shell to be spotted at what-