_Platina_, the heaviest of all metals, is nearly as white as silver, and difficultly fusible, though by great labor may be rendered malleable, so as to be wrought into utensils like other metals. It will resist the strongest heat of our fires without melting, and, like iron, is capable of being welded when properly heated. It is found in grains, in a metallic state, at St. Domingo: and also at Santa Fe, in Peru, in the language of whose inhabitants it means _little silver_. It has recently been discovered in an ore of silver found in Estremadura, existing in its metallic form. This metal was first introduced into England by Charles Wood, who brought it from Jamaica in the year 1741. It has been drawn into wire less than the two thousandth part of an inch in diameter. The specific gravity of hammered platina is 23.66, which is more than double that of lead. _Mercury_, in the temperature of our atmosphere, is a fluid metal, having the appearance of melted silver: in this state it is neither ductile nor malleable; very volatile when heated; extremely divisible; and is the heaviest of all metals except platina and gold. We see it always in a fluid state, because it is so fusible that a small portion of caloric will keep it in a state of fluidity; but when submitted to a sufficient degree of cold, is similar to other metals, and may be beaten into plates. It has been determined, that at 39 degrees below zero of Fahrenheit’s thermometer is the point at which the congelation of mercury takes place. In the winter of 1799, Mr. Pepys froze 56 pounds of it into a solid and malleable mass. At Hudson’s Bay, frozen mercury has lately been reduced to sheets as thin as paper, by beating it upon an anvil that had previously been reduced to the same temperature. It is a substance so volatile that it may be distilled like water; and is sometimes purified in this way from mixture with other metals, being often adulterated with lead and bismuth. It is also so elastic when in a state of vapor, that it is capable of bursting the strongest vessels. According to Mr. Biddle, its specific gravity at 47 degrees above zero is 13.545; but when frozen into a solid at 40 below zero, 15.612. This metal is brought to Europe from the East Indies and Peru; but is found in greater abundance at Almaden in Spain, where it is extracted from the ore by distillation. The quicksilver mine of Guanca Velica, in Peru, is 170 fathoms in circumference, and 480 deep. In this profound abyss are streets, squares, and a chapel where religious mysteries on all festival occasions are celebrated. Millions of flambeaux are continually burning to enlighten this subterranean abode. This mine generally affects those who work in it with convulsions. Notwithstanding this, the unfortunate victims of an insatiable avarice are crowded all together, and plunged _naked_ into this abyss. Tyranny has invented this refinement in cruelty, to render it impossible for any thing to escape its restless vigilance.