e
),
e
and
f
being to each other as object and image. The remaining sphere (7
b
) is identical with the highest in the calcium funnel. The remaining two spheres, one below the other, are identical with the corresponding two spheres in calcium. The central globe, as regards its external segments, is again identical with that of calcium, but in the internal segments a six-atomed triangle (7
k
) is substituted for the calcium four-atomed one (7