The trawler puts us aboard the depot ship; but the Admiral is not there. A picket-boat takes us over to his pier, and we find him in his chart-room, surrounded by maps marked with spots and figures in different colours, quite unintelligible except to those who have the key, and even to them no subject for conversation at large. But the Admiral is a good talker, his mind is an encyclopædia of submarine war and the working of a naval base, and he is amazingly quick in separating the facts which interest you, and yet are fit for repetition outside, from those which you must forget as soon as you have heard them. He begins by explaining the daily routine of the port--the mine-sweeping, which is done regularly twice a day, but at what times the enemy can only guess, and the mine-laying, which is a game of brain against brain, each side trying to see through the other’s devices and catch him with their own. An elementary example would be the obvious dodge of moving the enemy’s mine a short distance, instead of removing it altogether--so that when next he comes that way, he shall run into it unexpectedly, and perish by his own trap. But this, as I have described it, is too simple a device to be successful, and the ingenuity of our mine-layers has improved upon it by a dozen skilful variations. Much can be done by studying carefully the habits of the German mind. One officer, who is specially skilled in this matter, has the credit of being able to make a U.C.-boat lay her eggs just where he pleases, and of knowing exactly when it will be time to go and collect them. Our own mine-laying and coastal patrol would be more exciting if the possible successes were not limited to an occasional submarine. It is a little dull to be always laying traps for a flotilla that never comes. The work of our coastal submarines is therefore monotonous; but it is none the less invaluable. Besides making sure, it trains a continual succession of crews for oversea work, and gives experience to young commanders. The number of boats increases every year, and the flow of volunteer entries keeps pace with it. The standard demanded is very high, and it is fully maintained. The prize of efficiency is immediate entry into the hardships and dangers of the oversea patrol.