But on the stairway descending from the south of this plateau, and on the spurs reaching up from the coast on the east, all this is reversed. The approach of an army acting on the offensive, uphill or across the series of ridges, is commanded by so many points, that a small number of defenders can readily arrest its advance. Position leads but to position, and these, prolonged almost indefinitely on either flank, are not readily turned, or, if turned, still offer locally a strong frontal defence, should the enemy be sufficiently mobile to reach them in time. Streamlets, which would be negligible on the plateau, become formidable obstacles in their deep beds. The horseman's occupation is greatly limited, for he can neither reconnoitre nor gallop. Marches must, therefore, be made painfully in battle formation, for every advance may entail an action. Thus strategy is grievously cramped by the constant necessity for caution, and still more by the tedious movements of the mass of transport, without which no army can continue to operate in a country sparsely inhabited, and as sparsely cultivated. [Sidenote: Variety of rainfall.] In South Africa even the rainfall militates against concurrent operations on a wide scale, for, at the same season of the year, the conditions prevalent upon one side of the sub-continent are exactly the opposite to those obtaining on the other. In the western provinces, the rainy season occurs in the winter months (May--October), in the eastern, including the Boer States, the rain falls chiefly in the summer (October--March). Yet so capricious are these phenomena that a commander, who counted absolutely upon them for his schemes, might easily find them in abeyance, or even for a period reversed. [Sidenote: Variety of S.A. climate.] Beyond the broad facts stated above, the extent of South Africa renders it as impossible to specify any typical climatic or scenic peculiarities common to the whole of it, as to fix upon any strategical or tactical character that is universal. Cape Colony alone exhibits such antitheses of landscape as the moist verdure of the Stormberg and the parched dreariness of Bushman and Little Namaqua Lands, and a rainfall ranging from two to seventy-two inches per annum. The variations in other parts are little less striking. The temperature of the High Veld, for instance, is wont to rise or fall no less than sixty degrees in twelve hours, or less. Thus, whilst one portion of an army on a wide front might be operating in the tropics, another might be in the snows, whilst a third was sheltering from the sun by day, from the frost by night, conditions which actually obtained during the contest about to be described. What effect such divergencies must exercise on plans of campaign, on supplies of clothing, shelter, food, forage, and on military animals themselves, may be readily imagined. CHAPTER IV. THE BOER ARMY. [Sidenote: Many previous cases compare with Boer resistance.]