Both the Germans and ourselves used huge mine-charges in the chalk and the effect of the explosion of many big mines is spread over a large area. We always felt the shakes in the ground even back in our dugouts at Aux Rietz, over a mile away; while in the forward trenches we had all the excitement of a regular earthquake. All dugouts would shake badly, timbers would be loosened and many men buried in other dugouts and shelters, while sleeping. The firing of mines at night or just about dawn was a favorite practice. Just about the time you have turned in on the floor of your dugout to get an hour's badly needed rest, the earth is shaken by a heavy mine explosion. Pleasant dreams of your home in California's land of sunshine and flowers are rudely interrupted. You grab your tin hat, gas-helmet, electric torch, and hurry up the steps to the dark, ghostly trench. Often it is raining hard and none of the sentries on duty in the trench above know exactly where the mine has gone up. Sloshing through the muddy trenches and dodging the trench-mortar and machine-gun fire which always form a part of the programme in a Boche "blow," you reach the scene of the explosion as fast as you can, fearing the worst, but often relieved to find that your boys are all right and that only minor damage has been done to your galleries. After visiting your own mines, you come up again to be met with a report that several bombing sentries have been buried in their trench as a result of the mine shake. Rescue-parties are hastily organized, and endeavors are made to reach them under a perfect hail of bullets, all working frantically to dig them out from the thick mud and slimy sand-bags. Sometimes we are successful. Many times I have heard the poor fellows call for help, but despite all our efforts, we could not always reach them to dig them out before they were fatally injured or completely buried. I have experienced the sensation of being buried and partly buried by shell explosions as well as mine explosions at different times. The first few minutes before you are dug out are not pleasant ones.

The opposing trenches here were very close in places. Where craters had been blown, the Boche would often occupy one rim and our fellows the other. Some of the smaller craters were only about fifteen to twenty yards wide. Curiously enough, the fighting at these points was not as fierce as might be inferred. It seemed to be a case of waiting for the other fellow to start something.

Most of the craters, big and small, were more or less consolidated by building narrow, winding trenches out to them from the front lines, and then cutting trenches in the rims. Sentries would be posted at good observation-posts overlooking these craters, and it was an unhealthy practice to take your evening stroll there. In the course of my duties it has been my misfortune to be reconnoitring these craters on some occasions when bombs or T.M.'s have burst in them, and the sensation is not pleasant, although one is not so likely to be buried as when shells or mortars burst near in a trench. There is no cover of any kind to be had. Those craters near our lines would be very useful to us as they would serve as receptacles into which we could dump our spoil. A number of the trenches here, as elsewhere, ran right across No Man's Land from the Hun lines to ours, and these would be blocked on both sides in some way or other, either with barbed wire or breastworks of sand-bags, etc.

Our advanced billets were within 100 yards of the villages of Neuville-St.-Vaast and La Targette. Both of these villages were levelled by enemy fire, nothing remaining but a mass of ruins. All the cellars were used by troops as billets. We were lucky enough to get a very decent old French officers' dugout by the side of the road, with about six to seven feet of earth cover. The timbers of the structure were substantial, and lucky it was for us that they were for we were very heavily bombarded by the Hun artillery. Our men had very curious billets. In this part of France and for some distance south the subsoil is a hard chalk, and this has been quarried underground nearly everywhere, leaving a clay top-soil and good grazing-land above. The houses and buildings are constructed of chalk building-blocks with brick foundations. Every house, also, no matter how small, has a cellar. These cellars are not proof against direct hits with enemy artillery, but they can be easily reinforced and are exceedingly useful in any case.

Chalk caverns are numerous, and one of the large variety was handed over to us as a billet for our men. Although our entire company was about 600 strong, we had plenty of room for 400 or 500 extra men in this cavern, and for a long time we took care of over a thousand there. It was in decidedly bad condition when it was turned over to us. The air could almost be cut with a knife at that time; however, we put in another upcast and managed to clean it up as well. As it was over 70 feet deep, there was no loss of sleep from enemy-shelling activity. Stories were current as to a big fight which had occurred down in this cavern in the previous September, and I should judge that there was some truth in the report, on account of the large French cemetery at the crossroads above and the number of bodies which we unearthed below in the cavern.

These caverns exist almost everywhere in Artois, Picardy, and the Somme district. Under nearly every church there are big caverns or crypts. At Foncquevillers in some large crypts under the church we stored millions of bombs and trench-mortars, and stores of ammunition, altogether sufficient to blot out the whole of the German army. An interesting way of salvaging and sorting the Mills hand-grenades in one of those crypts was practised here. The bombers would sit around a circular iron tank nearly filled with water. Halfway up the sides of the tank clay sand-bags were placed. When a bomb-fuse started to fizz, the bombers would quickly drop it in the tank, where it would explode at the bottom and do no harm. Some of these caverns existed also right in our support-line trenches, and it was common opinion that old galleries in the chalk ran under No Man's Land and across to the German lines.

The ruins of an old mill located just behind our firing-line was suspected of having a cave under it. Upon investigation we found that old tunnels formerly existed there but had caved in. However, the enemy had so many tunnels all around us that it kept us jumping sideways to keep informed as to all of them. This mill was a favorite target with the Hun, and therefore not a popular rendezvous for us. Some very stout-hearted gunner officers had adopted it as an O.P. (observation-post), and had reinforced it with a strong corrugated-iron elephant frame. No one disputed their claim to it. A few days after, the whole business, frame and all, went up in smoke as the result of a direct hit with a Boche eight-inch. It is a custom for engineer and artillery officers to "spy out" the land around the trenches by day and night, intent on their own fell designs, often alone, in distinct disregard of existing orders, which do not allow officers to make their rounds in the trenches unaccompanied by an orderly or N.C.O. Mining officers in particular were the worst sinners in this respect, and our men were often arrested and very nearly shot before they established their identity.

I met one of my own N.C.O.'s one day coming along the firing-line closely following an officer whom he had suspected of being a spy. The officer's hands were held high above his head, while B., usually a quite mild, inoffensive sort of chap, was threatening him fiercely with a jab from his bayonet if he opened his mouth or made any strange move. The situation was highly amusing. The young officer was protesting strongly against such treatment. It appeared that my man had caught him below in one of our mines asking foolish questions. We took him along to the nearest company headquarters' dugout and let him go after he had satisfied us that he was all right. I'm willing to bet that he didn't attempt any more mine explorations without proper credentials.

My only experience with a real spy was in these trenches. One day I met a very pleasant-spoken artillery officer, had a few words with him as he passed my dugout, and offered him a drink, which he refused politely. It may have been fortunate for me that I was called away hurriedly to attend to some work. Later in the day I heard that my acquaintance of the morning had turned out to be a German spy, and, I understand, was lined up against a wall a few days later. He had what I thought was one of the most natural British accents I have ever heard.

In taking over the troublesome galleries below ground from the French, they had neglected to provide us with any surveys of the mine system, so it was necessary for us to make some. Our usual method was to use a compass and a fifty-foot tape and make surveys between all mine-shafts and then carry them below. The work below was all right, but in the trenches above the necessity of keeping one eye on the compass and the other constantly on the lookout for trench-mortars was rather disconcerting, and many readings and measurements had to be repeated. It was a case of "let George do it" when surveys of any close-up trenches had to be made, and the newest joined officer usually found it included in addition to his other duties.

The charges we used in our deep mines in the chalk were tremendous, mine-chambers being loaded with anything from 1 up to 50 tons of a high explosive twice as strong as dynamite. Last year in the battle of Messines the British launched their first big attack by firing a large number of mines below the enemy trenches, using charges of from 15 to 50 tons in each mine and exploding them all at the same moment, the "zero" minute, or exact time at which the infantry go over the top. Very close to a million pounds of a remarkably high explosive were fired at the same instant by the engineers on this front. In starting an infantry attack the mining officers, in common with all the officers of the units engaged in the attack, synchronize their watches, and at the second planned, push home hard the handles of their blasting-machines. Earth-racking mines are detonated with terrific force. The craters formed from these explosions are often over 300 feet in diameter and from 50 to 150 feet deep. Whole companies of men are engulfed, all trenches within a large radius totally destroyed, and many additional men buried in their fall.

So intense was the fighting below ground in our operations on the Vimy Ridge that we would explode sometimes as many as 4 separate mines a night on our own small company front, only 500 yards in length of sector. In one of our clay galleries we reached the enemy trenches and, passing under them, ran into the timber of one of their mining-shafts. Carefully cutting a small hole through one of their timbers we listened there, relieving each other from time to time for nearly twenty-four hours. We would carefully crawl up to our listening-hole and sit tight in the dark, hardly daring to breathe. We had struck the bottom of the Boche shaft and could hear them talking and even see occasionally the enemy miners as they passed up to their own trenches. Our knowledge of German was unfortunately extremely limited, but no interpreters could be obtained or persuaded to join us at this spot. I can't blame them. We finally fired this mine and three others also under their front line at the same time, blowing their trenches and many Huns sky-high. A small party from the "Black Watch" followed over on a fast raid and reported on their return that very little trace of enemy trenches could be found for 200 yards, everything having been totally destroyed by our mines.

Another time we were tunnelling through with a four-foot-six-inch by two-foot-six-inch gallery in the clay, but right on top of the chalk formation. The floor of the gallery was only an inch or two above the chalk. The enemy workings must have been about ten feet below our gallery and in the chalk. We could hear them very plainly at work, so continued progress on our tunnel without a sound, and presently, as they came very close, could hear them talking. We then loaded a small charge, about a thousand pounds of high explosive, at the end of our gallery. Sitting tight and listening carefully, we waited until they had passed under and just beyond us. A few hours later the listeners reporting that they were at work again on the face of their gallery, we fired our camouflet with the blasting-machine from the trench above.

A camouflet is a small mine explosion which does not form a crater, and is calculated to destroy underground workings. One does not always have pleasant reflections after some of these operations, but we all stand the same chance. If the enemy fires first, we go up, and vice versa. So the game of wits below ground goes on. Sometimes we score, and sometimes Fritz outplays us.

One night a runner brought down the news to us at our dugout at Aux-Rietz that the Boches had fired a camouflet in our "H" mine on the extreme right of our sector. Everybody below had been killed from the resulting concussion and poisonous gases developed. Fortunately there were only seven sappers in the mine at the time. The officer on duty and three other men had gallantly attempted to rescue some of the poor fellows by going below in oxygen-breathing apparatus, but had themselves been gassed, and were only rescued with difficulty. After the gas below had dissipated sufficiently we were able to recover three of the bodies, but those of the other four men were never found. A Church of England chaplain came up a day or two later and read the usual short army burial service at the top of the mine-shaft, surrounded by a few of the comrades of the dead soldiers, the latter reverently attentive and much impressed with this unusual burial.

The enemy trench-mortar fire on the surface was particularly bad. We reached a stage where we thought nothing of shelling as long as they did not throw in a number of T.M.'s, as they are called. These trench-mortars vary in weight from 5 to 250 pounds, from aerial darts to heavy minenwerfers. Their trajectory being steep and their velocity not very high, we could see them turning over and over like a football in the air, look out for them, and in many cases reach cover before they dropped. However, this was not easy. One could always see the trench-mortar which was going to land in a trench about a hundred or more yards distant, but those T.M.'s which were coming straight for you kept us guessing as to whether they would land in our fire-bay or the next. We usually guessed wrong.

Our casualties from these trench-mortars were heavy. Ten of my men were coming in to report for duty one afternoon. They were working at mine "F," and the trenches by which we approached this shaft were always subjected to intense bombardment with T.M.'s, and at many places almost completely levelled by this fire at regular intervals. When this happened the wise man would bend almost double in passing along or crawl over the obstruction on his hands and stomach so as to avoid observation. On this afternoon we concluded that some of our lads had exposed themselves in going up, or that the Boches had located the entrance to our shaft. Directly they reached the entrance a heavy trench-mortar burst among them, killing six and wounding another. Four of the bodies were hurled down the shaft.

These T.M.'s are bad things—the burst results in inflicting multiple wounds. I have seen a number of poor fellows hit in over twenty places from one T.M. The medical people have a busy time fixing them up. Many, however, recover.

Another time in coming up a communication-trench we found the body of one of our boys lying in the bottom of the trench, evidently hit only a few minutes before. The poor chap was dead, but curiously enough we could only find one wound—that in his shoulder. He must have been killed by the shock of the explosion. The T.M. had burst about five feet from him. In my experience this has seldom happened, but I understand there are many authenticated cases.

As in the infantry, the majority of our casualties occurred from day to day, from one to two or three and more almost daily. At any rate it does not take long in every-day trench warfare to lose half of any company.

At other times, when, for instance, troops are relieving other units in the trenches, or perhaps in large parties at crossroads coming up, the casualties from shelling are very large. One night in Flanders a party of our men were going up the communication-trench when a Boche five-point nine (5.9) burst on the parapet near them. Of this small party of thirty, only fifteen went on to the front line, seven being killed and eight wounded. At the crossroads entering HÉbuterne from Sailly, a particularly hot place, and one that I know very well, having been billeted in a cellar within a hundred yards from it during two winter months I have known as many as seventy casualties from one shell-bursting. Every day one either sees or hears of large or small parties being blotted out by enemy shelling.

The division we were with provided us with working-parties day and night to assist us. Usually the parties came from the infantry, though the cavalry were also used a good deal. Here we received parties from the cavalry, infantry, and cyclists. As I understand it, the cyclists are intended to support and relieve the cavalry at night on the few occasions when they can be used in open warfare. I don't think they had the chance very often. So far the cavalry have been out of luck in this war. Both the cavalry and cyclists have been doing trench duty now for a long time.

On the Vimy Ridge a number of East Indian cavalry units were given us for working-parties. These were mostly regiments of lancers, and were composed of Sikhs, Rajputs, Pathans, and many other tribes or sects of British Eastern India. The Sikhs were particularly fine men, tall, well built, quiet, and exceedingly dignified. They always wore their big white turbans. It is a mark of caste with them, and nothing will induce them to part with these or wear anything else. They even scorned the use of the steel helmets which had just been issued to us. We did not. Many of us, myself included, owe our lives to the use of these steel helmets. The other Indian troops always wore the steel helmet.

These native troops had what was to us a very unpleasant habit of carrying everything on their heads. We did not object to this procedure back of the line, but when they carried all the mine timbers and other supplies right to the fire-trenches in this manner we thought it wise to stop the practice before the Huns blotted us all out. Fritz would observe these little parties very easily by reason of the fact that the timber would invariably show above the top of the trench as they came up and would make us the target for a little more T.M. practice. I used to cut ahead across the top and jump down into a trench they would have to pass, and there make every man take his piece of timber from the top of his head and tuck it under his arm. These fellows did not like the T.M.'s any more than our boys did, but after a time treated them in the same casual, cheerful way as the others. I heard an infantryman once refer to these native troops, in the hearing of one of their British officers, in rather a disrespectful way. The way that officer lectured the offender was good evidence of the friendly relations existing between the British officers and their native troops. The latter, in turn, think a great deal of their British officers, and look after them with an almost fatherly solicitude. They had their own native officers also, many of them being sons of rajahs or native princes of India, educated for the most part in the big English public schools and colleges. The cavalry "brasshats" (as the British call all senior officers) of these units visited them often in the trenches. They were all in the trenches for the first time, and much interested in everything. So many of them called at our dugouts, and in company with us inspected our work and the trenches generally, that we felt like regular Cook's tourist guides. They were all mighty fine fellows and without exception aching to get a chance at the Hun, and chafing a great deal at their forced inactivity. They had hopes then of getting in a real charge in the possible open fighting of the coming Somme offensive.