It is always advisable to have the gun ready for any emergency at night, and the following will be found an effective method of preparing the sights for aiming in the dark. Cut a piece of white paper, previously prepared with luminous paint, into the shape of a triangle, and paste it on the slide of the tangent sight so that the apex of the triangle touches the bottom of the V of the sight. Cut also a circular piece of a size that will fit on the foresight just below the tip, and paste this on the foresight. On looking over the sights in the dark, when the luminous ball on the foresight is seen resting on the apex of the luminous triangle on the tangent sight, the gun will be truly laid for the range for which the sight is set. Machine guns with the local reserves must be light and mobile; they will be used in a similar way to those with infantry, and to assist in counter-attacks, particularly against the advanced infantry positions and sap-heads of the besiegers. They may also have opportunities of enfilading a trench or firing into a work that has been captured by the enemy. When used for this purpose they must be brought up by hand under cover and open fire at close range from a position that commands the interior of the trench or work, and if possible enfilades it. Great risks are justified in bringing up machine guns for this purpose, as the results of a successful fire action will usually be decisive and far-reaching. The following is an example of their use in this manner during the siege of Port Arthur: “On the attack on 203-Metre Hill, machine guns on Akasakayama flanked the position and enfiladed the attackers. Four hundred Japanese were sheltered together in a parallel, where they were completely screened from fire from any part of 203-Metre Hill. Suddenly two machine guns, _which had been concealed on Akasakayama, where they could fire directly into the parallel_, opened fire. Within a few seconds it was turned into a veritable pandemonium, a seething mass of humanity, where men were wildly fighting to get away, trampling on the wounded, climbing over piles of corpses which blocked the entrance, and trying to escape down the coverless hillside. But the Maxims did their work as only Maxims can, and within a few moments practically the whole force was wiped out; a few men were shot dead as they ran down the hillside, but nearly all the others were killed in the narrow trench. It took the Japanese days to extricate and carry away the fearfully intermingled corpses.”[42] There are so many instances of the successful use of machine guns in the defence of Port Arthur that it will be impossible to quote more than a few of the most striking to illustrate the principle on which they should be employed.