The water had a greenish hue, and its surface was very brilliant. To the taste, the travelers found it intensely and intolerably salt, and far more nauseous than the waters of the ocean. The great quantity of saline matter, which it contains, makes it very dense, and, of course, very buoyant in respect to bodies floating in it. This property of the sea has been observed and commented upon by visitors in every age. Swimmers, and those who can not swim, as an ancient writer expressed it, are borne up by it alike. Robinson himself bathed in the sea, and though, as he says, he had never learned to swim, he found, that in this water he could sit, stand, lie, or float in any position without difficulty. The bottom was of clean sand and gravel, and the bathers found that the water shoaled very gradually as they receded from the shore, so that they were obliged to wade out many rods before it reached their shoulders. Its great density produced a peculiar effect in respect to the appearance that it presented to the eye, adding greatly to its brilliancy, and imparting a certain pearly richness and beauty to its reflections. The objects seen through it on the bottom appeared as if seen through oil. MEASUREMENTS. After having spent some time in noting these general phenomena, Robinson, finding that the day was wearing away, called the attention of his party to the less entertaining but more important work of making the necessary scientific measurements and observations. He laid off a base line on the shore, fifteen hundred feet in length; and from the extremities of it, by means of a large and accurate compass, which he carried with him in all his travels for this express purpose, he took the bearings of all the principal points and headlands which could be seen around the sea, as well as of every mountain in view. By this means he secured the data for making an exact map of the sea, at least so far as these leading points are concerned; for, by the application of certain principles of trigonometry, it is very easy to ascertain the precise situation of any object whatever, provided its precise bearing from each of two separate stations, and also the precise distance between the two stations is known. Accordingly, by establishing two stations on the plain, and measuring the distance between them, and then taking the bearings of all important points on the shores of the sea, from both stations, the materials are secured for a correct map of it, in its general outline.