Before setting out on our third journey to Sebituane, it was necessary to visit Kuruman; and Sechele, eager, for the sake of the commission thereon, to get the ivory of that chief into his own hands, allowed all the messengers to leave before our return.  Sekomi, however, was more than usually gracious, and even furnished us with a guide, but no one knew the path beyond Nchokotsa which we intended to follow.  When we reached that point, we found that the main spring of the gun of another of his men, who was well acquainted with the Bushmen, through whose country we should pass, had opportunely broken.  I never undertook to mend a gun with greater zest than this; for, under promise of his guidance, we went to the north instead of westward.  All the other guides were most liberally rewarded by Mr. Oswell.

We passed quickly over a hard country, which is perfectly flat.  A little soil lying on calcareous tufa, over a tract of several hundreds of miles, supports a vegetation of fine sweet short grass, and mopane and baobab trees.  On several parts of this we found large salt-pans, one of which, Ntwetwe, is fifteen miles broad and one hundred long.  The latitude might have been taken on its horizon as well as upon the sea.

Although these curious spots seem perfectly level, all those in this direction have a gentle slope to the northeast:  thither the rain-water, which sometimes covers them, gently gravitates.  This, it may be recollected, is the direction of the Zouga.  The salt dissolved in the water has by this means all been transferred to one pan in that direction, named Chuantsa; on it we see a cake of salt and lime an inch and a half thick.  All the others have an efflorescence of lime and one of the nitrates only, and some are covered thickly with shells.  These shells are identical with those of the mollusca of Lake Ngami and the Zouga.  There are three varieties, spiral, univalve, and bivalve.

In every salt-pan in the country there is a spring of water on one side.  I can remember no exception to this rule.  The water of these springs is brackish, and contains the nitrate of soda.  In one instance there are two springs, and one more saltish than the other.  If this supply came from beds of rock salt the water would not be drinkable, as it generally is, and in some instances, where the salt contained in the pan in which these springs appear has been removed by human agency, no fresh deposit occurs.  It is therefore probable that these deposits of salt are the remains of the very slightly brackish lakes of antiquity, large portions of which must have been dried out in the general desiccation.  We see an instance in Lake Ngami, which, when low, becomes brackish, and this view seems supported by the fact that the largest quantities of salt have been found in the deepest hollows or lowest valleys, which have no outlet or outgoing gorge; and a fountain, about thirty miles south of the Bamangwato—­the temperature of which is upward of 100 Deg.—­while strongly impregnated with pure salt, being on a flat part of the country, is accompanied by no deposit.