1. 夜間視力鍛錬の重要性

At night, one is able to see according to the degree of darkness. The amount of vision also differs naturally and it is important to know the amount under various circumstances. Especially is this true under circumstances where the judgment cannot be formed by hearing, i. e., in rainy weather, or under other noisy conditions, where vision, though insufficient, is superior to hearing. Therefore, the training of the eye at night is a most important matter, as, to a certain degree, it can be strengthened by experience and practice. In the Japanese-Russian War, the judgment by sight of soldiers accustomed to the terrain and to night movements, was surprisingly good, and was entirely due to experience.