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Atomic weight 93.25
Number weight 1719/18 95.50
III a.--Aluminium, gallium and indium were examined from this group. They
are triatomic, diamagnetic, and positive. The corresponding group contains
phosphorus, arsenic and antimony: bismuth also belongs to it, but was not
examined; they are triatomic, diamagnetic and negative. They have no
central globes.

[Illustration: PLATE XIII.]

ALUMINIUM (Plate XIII, 1), the head of the group, is, as usual, simple.
There are six similar funnels, each containing eight ovoids, below which is
a globe.

ALUMINIUM: 6 funnels of 81 atoms 486
Atomic weight 26.91
Number weight 486/18 27.00
GALLIUM (Plate XIII, 2) has two segments in every funnel; in the segment to
the left a "cigar" balances a globe, equally six-atomed, in that of the
right, and the globes to right and left are four-atomed as against
three-atomed. In the next row, the smaller contained globes have six atoms
as against four, and the cones have respectively seven and five. By these
little additions the left-hand funnel boasts one hundred and twelve atoms
as against ninety-eight.

GALLIUM: Left segment 112 atoms }
Right segment 98 " } = 210
6 funnels of 210 atoms 1260
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