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 Bismuth, Bi, Poor Metal. For the purposes of analysis, bismuth. Bismuth readily forms alloys with other metals whereby, in accordance with the general law, the melting point sinks. The combining weight of bismuth has been determined by weighing the metal and the oxide obtained from it. It is not known with perfect certainty, and we shall take it as Bi.

Element Germanium, Ge, Metalloid. Matched those of the eka-silicon whose existence had been predicted in 1871 by Dmitri Mendeleev. By mass, more than that of Antimony, Silver and Bismuth.

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 Lead, Pb, Poor Metal. Calcium, which exhibits relations of isomorphism in both directions, stands in the middle. On the other hand, lead is decidedly a heavy metal, and forms an insoluble, dark-coloured sulphur compound. The combining weight of lead has been determined by the conversion of the metal into the oxide, and vice versa. It has been found to be Pb. Greeks called it molybdos; the same n.