The fact that Russia was ill supplied with railways, and hardly supplied at all with hard roads (in a climate where the thaw turned her deep soil into a mass of mud) is political rather than geographical, but it must be remembered in connection with this difficulty of supply.

If these, then, were the various disadvantages which geographical conditions had imposed upon the Allies, what were the corresponding advantages?

They were considerable, and may be thus tabulated:—­

1.  The western Allies stood between their enemies and the ocean.  If they could maintain superiority at sea through the great size and efficiency of the British Fleet, and through its additional power when combined with the French, they could at the least embarrass, and perhaps ultimately starve out the enemy in certain essential materials of war.  They could not reduce the enemy to famine, for with care his territories, so long as they were not ravaged, would be just self-supporting.  The nitrates for his explosives the enemy could also command, and, in unlimited quantity, iron and coal.  But the raw material of textiles for his clothing, cotton for his explosives, copper for his shell, cartridge cases, and electrical instruments, antimony for the hardening of the lead necessary to his small-arm ammunition, to some extent petrol for his aeroplanes and his motor-cars, and india-rubber for his tyres and other parts of machinery, he must obtain from abroad.  That he would be able in part to obtain these through the good offices of neutrals was probable; but the Allied fleets in the West would certainly closely watch the extent of neutral imports, and attempt, with however much difficulty and with however partial success, to prevent those neutrals acting as a mere highroad by which such goods could pass into Germany and Austria.  They would hardly allow, especially in the later phases of the war, Italy and Switzerland, Holland and Scandinavia, to act as open avenues for the supply of the Germanic body.  Though they would have to go warily, and would find it essential to remain at peace with the nations whose commerce they thus hampered and in some sense controlled, the Allies in the West could in some measure, greater or less, embarrass the enemy in these matters.

Conversely, they could supply themselves freely with tropical and neutral goods, and even with munitions of war obtained from across the ocean, from Africa and from America.

So long as North-western France and the ports of Great Britain were free from the enemy this partial blockade would endure, and this freedom of supply for France and Britain from overseas would also endure.

2.  The Allies had further the geographical advantage of marine transport for their troops—­an important advantage to the French, who had a recruiting ground in North Africa, and to the British, who had a recruiting ground in their dominions oversea, and, above all, an advantage in that it permitted the constant reinforcement of the continental armies by increasing contingents arriving from these islands.