I should note, perhaps, that while in the West the Allies' and the German trenches are said to often be within a few yards of each other, this was seldom the case in the East. There was generally a considerable space between the two lines: here near Skyermevice it amounted to 3,000 yards; but the Germans had advanced trenches in which they massed their men when about to make an assault. Evidently trench warfare is not so highly developed or so much resorted to in the East as it appears to be in the West. The vast numbers of the Russians, and the circumstance that the scene of actual fighting is constantly shifting over a very long front, are the probable causes of this. Another cause was the extreme hardness of the earth, which made it impossible to dig fresh trenches during the winter-time. It has been said that there is no such word as "impossible" in the military vocabulary; but the forces of Nature are frequently not to be overcome, even by military pluck and perseverance. Not even a soldier can dig holes in solid steel; and the ground in Poland was hardly less solid and difficult to work: hence trenches were not made after the early days of December, nor the dead buried as a rule. Field-works were made in various ways. Abattis, covered with barbed wire, were very common; and batteries formed of sand-bags; but neither were very successful. High explosive shells dashed the trees of the abattis to atoms, and drove the fragments back on the defenders, causing many casualties; and something similar occurred in the case of the sand-bags, which were torn to pieces, and dashed right and left, blinding many men. So during the winter, the rule was to stick to the old trenches; or occupy those naturally formed by hollows of the ground, or the deep banks of water-courses, the streams of which were usually firmly frozen. As wet could not soak away through the frozen ground the condition at the bottoms of those trenches which had been occupied for any length of time was filthy in the extreme. Dirty water, blood and refuse, was being continually added to the loathsomeness already existing, and this, and the constant trampling of the men, prevented the freezing of the mass; and I consider it simply wonderful that there was no serious outbreak of sickness amongst us. But Russian doctors and Russian officers are becoming fully conscious of the value of sanitation amongst troops; and the soldiers were kept as clean and well looked after as circumstances would permit. Moreover, the huge numbers of men admitted of frequent changes of those serving in the trenches; and they were never in these miserable burrows for any great length of time.