The early forces in Europe subsisted merely by individual plunder, each man obtaining his food and forage as he could. Later, the central power provided certain places where supplies were collected by force. The next step in supplying armies was taken when it was found that the local resources could be drawn on to furnish supplies on payment. This provided a more certain and effective supply, and demanded fewer troops to be employed in collecting. This change had a far-reaching result. The fact that cash had to be paid for these purchases caused Supply to come under the Civil Finance Department. Hence we find in Cromwell’s army this Service controlled by the Treasury, as it continued to be down to the Crimean War, with ill results for the army. Transport was required to carry the supplies from the districts whence they were collected to the area occupied by the troops, where they were stored in magazines. The next step, therefore, was to increase the mobility of the army by providing additional Transport to move supplies from these magazines up to the fighting troops. The train which carried supplies was, during the sixteenth and seventeenth centuries, a mass of hired or pressed country carts and wagons, driven by wagoners on foot, and difficult to manage or move near the enemy. It was found that, unless organized under military control, the transport was not very efficient, and by the epoch of Napoleon both the Transport and the Supply Services had become more and more military in organization. But they were both still _Civil Services_, owing to the hold the Treasury had over them, from the fact that both entailed constant expenditure during war. During the nineteenth century the _Train_ which provided transport became in all armies a Military Organization, with enlisted drivers under regular officers; while Supply continued to be organized as a Department under Civil officials, as it still is abroad. This system tends to produce difficulties, as the Combatant Military Train Officers have to move Supplies under the instructions of the Civil Supply Officials, and in foreign armies it is found difficult in war to make both work in co-operation. The tendency is, in fact, to bring about the close union between these two Services, long since found desirable in England. In all armies there are _Transport and Supply Columns_ formed from the Train with the addition of Supply personnel. In England alone are both provided from one Corps, the _Army Service Corps_, and the description of the British Transport and Supply Services given in Part II. illustrates what is perhaps the best organization of these Services for war. 3. THE MEDICAL ORGANIZATION FOR WAR