=75.= =The Point of Attack.=--From the information originally in possession of the besieger, supplemented by that obtained by reconnoissance, a decision is made as to the fronts of the work or the particular detached works of the intrenched camp upon which the approaches are to be made. The portion selected in either case is called the “_point of attack_.” To reduce an intrenched camp, it will in general be necessary to capture at least two of the detached works and to silence the artillery fire of one or more on each side of those taken. In an attack upon a strongly-fortified enceinte, the least that is usually undertaken is to breach and capture one front with its adjacent outworks, and to silence the fire of those which enfilade the approaches and parallels or take them in reverse. In selecting the point of attack the first consideration is, that when taken, it shall afford material advantage to the besieger and give him a foothold from which further approaches may be driven, if necessary. This condition being fulfilled, the choice will result from a careful study of the nature of the works and site. Those forts or fronts resting upon precipices, bordering deep marshes or deep and rapid streams, or which are so placed that approaches upon them will be swept in flank and rear by the fire of the works, which cannot be silenced, are considered impregnable by the ordinary operations of the siege. Most serious difficulties are presented by those in which the adjacent works are so disposed and of such strength that they can be carried only in succession and by regular approaches; those provided with wet ditches in which strong currents can be produced, those with dry deep ditches, those which are mined, and those which present long lines nearly straight, or even concave to the attack, and covering a front nearly equal or even greater than can be occupied by the trenches of the besiegers. When the parallels and approaches have to be constructed upon ground sloping downward towards the work, in soil containing large stones, or in which the rock is close to the surface, in marshy ground or that containing much water or liable to be flooded, the difficulty of their construction and defilade are evident. The point of attack considered most favorable to the besieger is one which, fulfilling the first essential condition, is more or less salient, so that it can be partially surrounded, and which admits of the approaches being driven toward it in favorable soil, over ground sloping gently from the work, or gently rolling with the crests and valleys of sufficient difference of level to afford cover, and running generally in the direction of the parallels. A favorable location for parks, etc., with free, safe, and short communications between them, also has great weight in selecting the point of attack. SECOND PERIOD.