), and the external part, belonging to the encircling globe, shows the familiar "cigar" (7
d
). In this way 720 atoms are packed into the simple beryllium type.
CALCIUM: 4 funnels of 160 atoms 640
Central globe 80
----
Total 720
----
Atomic weight 39.74
Number weight 720/18 40.00
Strontium
(
, 3) shows a still further complication within the funnels, no less than eight spheres being found within each. Each of the highest pair contains four subsidiary spheres, with five, seven, seven, five atoms, respectively (7
e
,