“I was intending to ask you for some information on that point, Swinton.  There has been more than one irruption into the country from the natives to the northward.  Mr. Fairburn gave me a very fair idea of the history of the Cape colony, but we were both too much engaged after our arrival in Cape Town for me to obtain further information.”

“I will, you may be assured, tell you all I know,” replied Swinton; “but you must not expect to find in me a Mr. Fairburn.  I may as well remark, that Africa appears to be a country not able to afford support to a dense population, like Europe; and the chief cause of this is the great want of water, occasionally rendered more trying by droughts of four or five years’ continuance.”

“I grant that such is the case at present,” observed the Major; “but you well know that it is not that there is not a sufficient quantity of rain, which falls generally once a year, but because the water which falls is carried off so quickly.  Rivers become torrents, and in a few weeks pour all their water into the sea, leaving, I may say, none for the remainder of the year.”

“That is true,” replied Swinton.

“And so it will be until the population is not only dense, but, I may add, sufficiently enlightened and industrious.  Then, I presume, they will take the same measures for securing a supply of water throughout the year which have been so long adopted in India, and were formerly in South America by the Mexicans.  I mean that of digging large tanks, from which the water can not escape, except by evaporation.”

“I believe that it will be the only remedy.”

“Not only the remedy, but more than a remedy; for tanks once established, vegetation will flourish, and the vegetation will not only husband the water in the country, but attract more.”

“All that is very true,” replied Swinton, “and I trust the time will come, when not only this land may be well watered with the dew of heaven, but that the rivers of grace may flow through it in every direction, and the tree of Christ may flourish.”

“Amen,” replied Alexander.

“But to resume the thread of my discourse,” continued Swinton; “I was about to say, that the increase of population, and I may add the increase of riches,—­for in these nomadic tribes cattle are the only riches,—­is the great cause of these descents from the north; for the continued droughts which I have mentioned of four or five years compel them to seek for pasture elsewhere, after their own is burned up.  At all events, it appears that the Caffre nations have been continually sustaining the pressure from without, both from the northward and the southward, for many years.