140 TO THE COLONIA AND BUENOS AIRES.
anchor some 500 miles up the Parana head-waters of the Plate^ sent solemn peremptory orders to steam^ with slack cable, round the missing mud-hook, " water and tide serv- ing.'* Impossible ! you will exclaim. Yet it is textually true, although methinks I hear Rear-Admiral Jock Trun- nion exclaiming, as he often has exclaimed upon his quarter- deck, that it is a " dom' lee."
Midway we pass the huge Ortiz Bank, which occupies more than half the river's breadth, and which is separated from the northern shore by a string of deep pools. In the excellent map of Captain Mouchez', it projects an angle to the south-east ; the Hydrographical survey makes it a long oval disposed north-west to south-east. The formation is sand upon " tosca," in Spanish a generic term meaning any imperfect stone. Here it is a rotten friable sandstone, with nodules of hardened and compacted clay. Sometimes it is applied to these nodules only ; at others it is a layer of tufa, or sand mixed with comminuted shells, and effervescing kindly under acids. The latter is useful as a compost to correct the huraic and ulmic " sourness" of a virgin soil in a subtropical climate. Presently we shall see the " Piano toscoso" below the Meseta or table-land upon which the city of Buenos Aires is built.
As the even shadow lengthens, a small white patch on a promontory pushing out to starboard proves to be the Nova Colonia do Sacramento, where the Major Estuary ends, and whence the Minor section stretches to the mouths of the rivers Parana and Uruguay. When mirage upraises it, and Fata Morgana upturns it, Colonia is visible from Buenos Aires ; but the big port must look out for squalls.
A strange, eventful history has that tiny white sheet, again and again stained with streams of man's life blood, tepid and impure. The " endless question" of the Colonia was pretty familiar to Englishmen between the days of Swift and Southey ; now it is utterly forgotten. Very
