At a certain point in our front our advanced trenches on the north of the Aisne are not far from a village on the hillside, and also within a short distance of the German works, being on the slope of a spur formed by a subsidiary valley running north and the main valley of the river. It was a calm, sunny afternoon, but hazy; and from a point of vantage south of the river it was difficult exactly to locate on the far bank the well-concealed trenches of either side. From far and near the sullen boom of guns echoed along the valley and at intervals, in different directions, the sky was flecked with the almost motionless smoke of anti-aircraft shrapnel. Suddenly, without any warning, for the reports of the distant howitzers from which they were fired could not be distinguished from other distant reports, three or four heavy shells fell into the village, sending up huge clouds of smoke and dust, which slowly ascended in a brownish-grey column. To this no reply was made by our side. Shortly afterwards there was a quick succession of reports from a point some distance up the subsidiary valley on the side opposite our trenches, and therefore rather on their flank. It was not possible either by ear or by eye to locate the guns from which these sounds proceeded. Almost simultaneously, as it seemed, there was a corresponding succession of flashes and sharp detonations in a line on the hill side, along what appeared to be our trenches. There was then a pause, and several clouds of smoke rose slowly and remained stationary, spaced as regularly as a line of poplars. Again there was a succession of reports from the German quick-firers on the far side of the misty valley and--like echoes--the detonations of high explosive; and the row of expanding smoke clouds was prolonged by several new ones. Another pause, and silence, except for the noise in the distance. After a few minutes there was a roar from our side of the main valley as our field guns opened one after another in a more deliberate fire upon the position of the German guns. After six reports there was again silence, save for the whirr of the shells as they sang up the small valley, and then followed the flashes and balls of smoke--one, two, three, four, five, six, as the shrapnel burst nicely over what in the haze looked like some ruined buildings at the edge of a wood.