Element Antimony, Sb, Metalloid. Is allied on the one hand to bismuth, and on the other, to arsenic and phosphorus. It therefore forms a transition element between the metals and the non-metals, but is still essentially on the side of the metals. Its combining weight is Sb. Probably, therefore, we are dealing with a mixture of different kinds of vapour, perhaps Sb. Is known from high antiquity. Oriental countries were familiar with Antimony.

Element Arsenic, As, Metalloid. In accordance with its smaller combining weight, arsenic. Deviates still more than antimony from the type of the metals, and exhibits greater similarity to the non-metal phosphorus; at the same time the tendency to form acid compounds increases. In fact the resemblance of arsenic to phosphorus is so great that it might also have been treated along with that element among the non-metals. If the vapour of arsenic. At the same time, other kinds of amorphous arsenic are formed.

Element Indium, In, Poor Metal. He came to conclusion that his atomic weight should be approximately 114, and its capacity to form alums means that this element belongs to Aluminium subgroup. May embed into their crystal grids.

Element Phosphorus, P, Non Metal. The name phosphorescence, used in physics for the after luminescence shown by certain substances after a previous exposure to light, is a relic of that usage. At the present day, the name phosphorus. The nerve and brain substances, more especially, are comparatively rich in phosphorus, which is there .

Element Silicon, Si, Metalloid. Silicon stands to carbon in the same relation as sulphur to oxygen. The two elements are similar in many respects, but differ more from one another than, for example, chlorine, bromine, and iodine do. Like carbon, occurs in several forms, of which an amorphous and a crystalline form are accurately known. Amorphous silicon is obtained by conducting its chlorine or fluorine compound over heated potassium; the metal unites with the halogen, and the silicon.

Element Tin, Sn Stannum, Poor Metal. Has been used, since epochs of Homer and Moses. Alluvial aggradations are found much more often and may be processed much easier than other ores. Brythons were closely familiar with tin. As Cornwall slag hills testify.

Element Aluminium, Al, Poor Metal. Of all the light metals, aluminium. It forms a constituent of almost all crystalline silicate rocks; and of the secondary formations, the clays and slate formations are formed from aluminium silicate. A knowledge of the compounds of this metal, therefore, extends back as far as chemical knowledge at all can be traced. While, even at comparatively high temperatures, massive aluminium is only superficially and inappre.