While the full strength of the German army is given at 4,000,000 on a war footing, the total availables from the nation's reserve is double that sum. These forces are gathered from three sources: the first line, with an estimated strength of 1,750,000; the Landwehr 1,800,000, and the Landsturm 4,500,000. All who enter the service pass into the Landsturm after 19 years and remain until they are 45. The cavalry service is three years with the colors and four years in the army reserve. The horse artillery are subject to the same service, while those in other branches serve two years with the colors and five with the army reserve. The soldier passes from the army reserve into what is described as the Landwehr, where artillerymen and cavalrymen remain three years; those of other branches of the military five years. The soldier passes from the first division or class of Landwehr to the second, where he remains until his 39th birthday. The Landsturm of the first class includes those between the ages of 17 and 39, who have not reached the age of service, and those who have not been called into active service because the ranks were full and there was no room for them in the regular army. The second class includes those who have passed through the other branches and whose ages are between 39 and 45. There is a wide difference between the military organizations of the different countries. Whereas the United States army regiment approximates 1500 men, the German army regiment contains almost 3000. In the German army six battalions form an infantry regiment. Two regiments form a brigade, two brigades a division, and two divisions an army corps. There are 10 divisions composed of 3 brigades each, but of course the whole organization was augmented when war broke out. Adding the necessary auxiliary troops, viz: an artillery brigade of 12 batteries composed of 6 guns each--or 4 in the case of the horse Batteries--a regiment of cavalry of 4 squadrons, an engineer battalion, sanitary troops, etc., a German 3-brigade division at war strength numbers about 21,000, and an army corps--to which are further attached 4 batteries of howitzers and a battalion of rifles--about 43,000 combatants. The cavalry division is composed of 3 brigades of 2 regiments each and 2 or 3 batteries of horse artillery, a total of 24 squadrons and 8 to 12 guns. In a general way it may here be interpolated that the organization of an army is given in the military manuals as follows: INFANTRY. A squad is 8 men under the command of a corporal. A section is 16 men under the command of a sergeant. A platoon is from 50 to 75 men under a lieutenant. A company is 3 platoons, 200 to 250 men, under a captain. A battalion is 4 or more companies under a major. A regiment is 3 or more battalions under a colonel, or a lieutenant-colonel. A brigade is 2 or 3 regiments under a brigadier-general. A division is 2 or more brigades under a major-general.