with great difficulty across marshes and soft meadowland.

3. Various Forms of Construction.—One cannot pretend to give even a bare list of the varied and numberless erections for which our engineers have been responsible behind the Belgian front, to accommodate the fighting troops and auxiliary services and mitigate the scarcity of suitable quarters. For three years German guns have battered everything within range, and converted the humble, peaceful villages of Veurne-Ambacht into heaps of ruins. One must go far behind the front to find any premises that have still escaped shell-fire. In them have been established all the organisations which need not be actually in the lines, and there also are quartered as large a part as possible of the resting units. But they cannot hold all the troops not in the trenches; and it will readily be understood that battalions held in reserve and warned first in case of an attack, must be near enough to throw themselves into the fight without loss of time. The problem has been solved by building a large number of huts in each divisional sector; yet without grouping them so closely as to afford an easy mark to the enemy's guns and aeroplanes. So the hutments, capable of accommodating some 100,000 men and about 15,000 horses, have been scattered over the whole of the district occupied.

In addition, much has had to be done and many buildings have had to be erected, in order to secure the best possible conditions for the elaborate organisations of the medical service, even in the fighting zone. We have had to provide bombproof first-aid stations, dressing-stations, and field hospitals, in many cases quite close to the lines, under circumstances the difficulties of which have already been sufficiently emphasised.

Huge hospitals, with several thousands of beds, have had to be built from the foundations upwards for the reception of the wounded not able to endure removal to the rear. Furnes, the only town in the district, at first provided invaluable accommodation; but, when systematic bombardment of the city endangered even the lives of the poor wounded, the hospital services had to be transferred elsewhere. The splendid hospital at La Panne, Adinkerke, Hoogstade and Beveren-sur-Yser, have long been regarded as models of their kind, though their establishment was attended by serious difficulties. Every possible modern improvement has been turned to account in their equipment; and although within earshot of the never-silent guns, they have accomplished marvels which the greatest authorities on the subject have on many occasions unstintedly and rightly praised.

We may conclude by just mentioning the aviation and balloon parks, the necessary installations for the various technical services, and the repair shops for motor- and horse-drawn vehicles, all of which have been established in the advanced zone by the Belgian Army. The vast amount of labour represented by these undertakings is self-evident, as the district contained practically no supplies of the materials needed.

4. Artificial Screens.—Unless we were to be content to expose ourselves to grave inconveniences and suffer huge losses, it is obvious that we could not long tolerate the enemy's full command of a plain entirely devoid of any cover able to interfere with his observations. The only means of blinding him was to protect all our works with artificial screens, composed of branches, hurdles and canvas set or hung all over the area occupied. Viewed by an observer in the German lines, these screens overlap in such a way as to form a virtually unbroken barrier, impenetrable to the eye.

To the layman this picturesque solution of the problem may seem simplicity itself, because he does not take into account the trouble of establishing these screens. As usual, all materials have to be brought to the spot from the rear. Fabulous quantities of branches are transported to the front by rail or barge, then loaded on to vehicles and taken to the workshops, where they are converted into enormous screens to be placed in carefully selected positions by special gangs detailed for the purpose.

As the supply of branches is not enough to meet all requirements, our resourceful fellows make use of reeds cut in the marshes of flooded meadows, some of them adjacent to the enemy's lines. The reeds are tied into large bundles and carried on the back to the hurdle-works, there to be interwoven and arranged between suitable supports.

Many thousands of square metres of these artificial masks have been set up all over the great plain. But, unfortunately, they are as fragile as they are picturesque. The wind, which often rises to a gale in this coastal region, blows them down or makes yawning holes in them; so they need constant attention. However, our long-enduring men have worked so well that the enemy cannot now watch what goes on in our lines.

5. The Supply of Drinking Water.—By a peculiar irony of fate, although the Belgian soldiers live in a country so saturated with water that every possible means must be employed to combat it, they would die of thirst had not works of considerable magnitude been undertaken to provide them with water fit to drink. During the battle of the Yser, when complete disorganisation reigned among the supply services of our valiant but unlucky army, many of the men could quench their thirst only with the muddy and loathsome water of the ditches which served them as trenches. As soon as that tragic fight was over, the greatest precautions had to be taken to prevent an epidemic of typhoid fever decimating what remained of our army. The existing wells in the fighting area had been invaded by the brackish flood water, in which floated hundreds of corpses; while those in the districts not yet ravaged by fire scarcely sufficed for local needs.

So to the rear, as in other cases, we had to look for drinkable water, which must be got up to the front lines in spite of transport difficulties.

As soon as circumstances allowed, we began to sink an adequate number of wells; and while in some places our fighting men obstinately strove to protect their defensive works from the treacherous floods, in others our workmen dug and bored into the unkindly soil in search of a stratum yielding potable water, which was struck at a depth of 125 metres—sometimes even further down. This alone will give some idea of the obstacles that had at all costs to be overcome. Our desperate and unwearied efforts were happily crowned with success, and soon the whole army, including the many auxiliary services of the advanced zone, enjoyed an abundance of good water.

6. The Telephone System.—Everybody knows how very important the telephone has become during the present war; but even the most far-sighted people who had strongly urged the general employment of this essentially practical and rapid means of communication, had not anticipated the extraordinarily wide scope which was to be given it.

To-day the telephone is the real bond of union between all units serving at the front, from the observer crouching in his advanced post to the commander-in-chief. It links those who issue commands with those who obey them, the lowest with the highest, and makes it possible for all efforts directed towards a single end to be correlated most efficiently in the performance of the common task. If so bold a comparison may be permitted, the telephonic network is the nervous system traversing the huge body of an army in action. The best mode of showing the prime importance of this network is to give some figures, which certainly exceed all the calculations that the layman would be likely to make. Would he imagine, for instance, that, by about the middle of the year 1917, the telephone wires of a single sector held by the Belgians had a total length greater than half that of the equator, or exactly