On both Wednesday and Thursday the weather was so fine that many flights were made by the aviators, French, British, and German. These produced a corresponding activity among the anti-aircraft guns. So still and clear was the atmosphere toward evening on Wednesday and during the whole of Thursday that to those not especially on the lookout the presence of aeroplanes high up above them was first made known by the bursting of the projectiles aimed at them. The puffs of smoke from the detonation shell hung in the air for minutes on end, like balls of fleece cotton, before they slowly expanded and were dissipated. From the places mentioned as being the chief targets for the enemy's heavy howitzers, it will be seen that the Germans are not inclined to concentrate their fire systematically upon definite areas in which their aviators think they have located our guns, or upon villages where it is imagined our troops may be billeted. The result will be to give work to local builders. The growing resemblance of this battle to siege warfare has already been pointed out. The fact that the later actions of the Russo-Japanese war assumed a similar character was thought by many to have been due to exceptional causes, such as the narrowness of the theatre of operations between the Chinese frontier on the west and the mountainous country of Northern Korea on the east; the lack of roads, which limited the extent of ground over which it was possible for the rival armies to manoeuvre, and the fact that both forces were tied to one line of railroad. Such factors are not exerting any influence on the present battle. Nevertheless, a similar situation has been produced, owing firstly to the immense power of resistance possessed by an army which is amply equipped with heavy artillery and has sufficient time to fortify itself, and, secondly, to the vast size of the forces engaged, which at the present time stretch more than half way across France. The extent of the country covered is so great as to render slow any efforts to manoeuvre and march around to a flank in order to escape the costly expedient of a frontal attack against heavily fortified positions. To state that the methods of attack must approximate more closely to those of siege warfare the greater the resemblance of the defenses to those of a fortress is a platitude, but it is one which will bear repetition if it in any way assists to make the present situation clear. There is no doubt that the position on the Aisne was not hastily selected by the German Staff after the retreat had begun. From the choice of ground, and the care with which the fields of fire had been arranged to cover all possible avenues of approach, and from the amount of work already carried out, it is clear that the contingency of having to act on the defensive was not overlooked when the details of the strategically offensive campaign were arranged. V. *Technique of This Warfare.* [Made Public Oct. 9.]