138 TO THE COLONIA AND BUENOS AIRES.
on the waters; perhaps he means the crystals of selenitethat are washed out from the clay banks of the river Paraguay.
To-day, rarely enough, the distant hue of this grand re- servoir of a thousand streams looks tenderly blue, somewhat like the Mediterranean in cloudy weather. The colour is generally that of grey mud, and our paddles churn up yellow and thick brown water, which reminds us of the Brazilian streams. Full of vegetable matter, it never strains clear and colourless; some say it is good to drink, others, myself included, that it causes trouble. On board we drink the produce of Monte Video tapped by Norton^s American system of tube-pumps, published to the world by the Abyssinian campaign. Here men are not slow to import improvements ; the invention was at once tried, it succeeded in the Banda Oriental, but it failed in the province of Buenos Aires — where blessed with all the gifts of Plutus shall be the wight that invents water.
The proportion of silt in the estuary has never been ac- curately measured, but the element we can see is heavily charged. We may, then, assume the discharge of the Indus, whose proportions vary from 17 to 43-60 per cent, in time of flood. The average would be 217,250,000 of cubic feet per annum, or seventy square miles of surface one foot thick. The stream is felt at an offing of ninety miles, but its great specific gravity prevents the Plate from being a tidal river. In Maldonado Bay the water is so fresh that it makes a difi'erence of three inches in a ship^s draught. Off Monte Video there is said to be an under- current of salt water, as at Gibraltar Gut and Bab el Mandab ; the limit of the ebb and flow is laid down at the mouth of the little Sta. Lucia Biver, some nine to ten miles to westward of the city. Like the Mediterranean and the Caspian, it is subject to wind tides ; thus also the Suez Gulf being depressed by northerly winds for nine
