Along about four thousand miles of the various fronts this sort of thing was going on that morning.... 2 This Carso front is the practicable offensive front of Italy. From the left wing on the Isonzo along the Alpine boundary round to the Swiss boundary there is mountain warfare like nothing else in the world; it is warfare that pushes the boundary backward, but it is mountain warfare that will not, for so long a period that the war will be over first, hold out any hopeful prospects of offensive movements on a large scale against Austria or Germany. It is a short distance as the crow flies from Rovereto to Munich, but not as the big gun travels. The Italians, therefore, as their contribution to the common effort, are thrusting rather eastwardly towards the line of the Julian Alps through Carinthia and Carniola. From my observation post in the tree near Monfalcone I saw Trieste away along the coast to my right. It looked scarcely as distant as Folkestone from Dungeness. The Italian advanced line is indeed scarcely ten miles from Trieste. But the Italians are not, I think, going to Trieste just yet. That is not the real game now. They are playing loyally with the Allies for the complete defeat of the Central Powers, and that is to be achieved striking home into Austria. Meanwhile there is no sense in knocking Trieste to pieces, or using Italians instead of Austrian soldiers to garrison it. II. THE MOUNTAIN WAR 1 The mountain warfare of Italy is extraordinarily unlike that upon any other front. From the Isonzo to the Swiss frontier we are dealing with high mountains, cut by deep valleys between which there is usually no practicable lateral communication. Each advance must have the nature of an unsupported shove along a narrow channel, until the whole mountain system, that is, is won, and the attack can begin to deploy in front of the passes. Geographically Austria has the advantage. She had the gentler slope of the mountain chains while Italy has the steep side, and the foresight of old treaties has given her deep bites into what is naturally Italian territory; she is far nearer the Italian plain than Italy is near any practicable fighting ground for large forces; particularly is this the case in the region of the Adige valley and Lake Garda.