The extent to which a combination of physical fatigue and shortness of supplies in an inhospitable country may interfere with the efficiency of an army is well shown by Thiers ("Histoire du Consulat et de l'Empire") in regard to the conditions at the very outset of Napoleon's Russian campaign. The French troops arriving on the Niemen--at which point they were merely on the frontiers of Russia--were already overcome by the long marches they had made. They had no bread, no salt, and no spirits; their craving for food could no longer be satisfied by meat without salt and meal mixed with water. The horses, too, were out of condition for want of proper food. Behind the army a great number of soldiers dropped out of the ranks and had lost their way, while the few people they met in a scantily-populated district could speak nothing but Polish, which the wearied and famished men were unable to understand. Yet, under the conditions of former days, it was by troops thus exhausted by marches of hundreds of miles, done on, possibly, a starvation diet, that battles involving the severest strain on human energy were fought. When "living on the country" is no longer practicable, the only alternative for an army is, of course, that of sending supplies after it for the feeding of the troops; but when, or where, this has had to be done by means of ordinary road services, it has involved--together with the transport of artillery, ammunition and stores--(1) the employment of an enormous number of vehicles and animals, greatly complicating the movements of the army; and (2) a limitation of the distance within which a campaign can be waged by an army depending entirely on its own resources. The latter of these conditions was the direct consequence of the former; and the reason for this was shown by General W. T. Sherman in an article contributed by him to the _Century Magazine_ for February, 1888 (pp. 595-6), in the course of which he says:-- According to the Duke of Wellington, an army moves upon its belly, not upon its legs; and no army dependent on wagons can operate more than a hundred miles from its base because the teams going and returning consume the contents of their wagons, leaving little or nothing for the maintenance of men and animals at the front who are fully employed in fighting. There was, again, the risk when food supplies followed the army by road either of perishables going bad _en route_, owing to the time taken in their transport by wagon, or of their suffering deterioration as the result of exposure to weather, the consequence in either case being a diminution in the amount of provisions available for feeding the army.