202 
might rotate in concentric zones, separate from each other 
by an interval of space. It may be further conceived, that 
the rotating zones of elementary matter were of sufficient 
thickness to cause a difference of density between their 
upper and lower regions. That the zones were in a highly 
electrical condition, and that their mutual influence on each 
other, through the annular space between them, would 
induce opposite electrical conditions in their external and 
internal regions; all the inner and denser regions of the 
zones being in a negative, and the outer or rarer regions in 
a positive electrical condition. Each zone would then be in 
a condition to form an electro-positive, and an electro- 
negative element, which, on a subsequent condensation, 
would separate and form two zones of elements having 
dissimilar properties alternating with the other members of 
the same series. 
J ust as silver and sodium are the connecting links between 
Hg and Cu, and the alkaline metals Li, K, Rb, and Cs ; so do 
cadmium and magnesium connect lead and zinc with the 
alkaline earth metals glucinum, calcium, strontium, and 
barium, which I have classified as forms of H2 n. The 
classification of glucinum with the alkaline earth metals has 
only recently been made, but chemists are not yet agreed 
upon the atomic weight of this element, as it has been 
fixed at Gl=7 (Awdejew) and Gl= 9’4 (Reynolds). It may, 
however, be suspected from the anomalously high specific 
gravity assigned to glucinum (2T0) as compared with that 
of magnesium (sp. g. 1'74), and with their homologues of 
position Li. sp. g. 059, and Na. sp. g. 0 97, that this element 
has not yet been isolated in a state of purity.* By assigning 
to glucinum the atomic weight Gl=8, it enters as a multiple 
* Since this paper was written, MM. Nilson and Petterson have com- 
municated to the French Academy the results of their researches on the 
physical properties of glucinum, and have found for the metal a density 
equal to 1‘64, which, although still too high, the theoretical density being 
about 1*3, is less than that of magnesium, and, consequently, stands in 
the same order of density as lithium and sodium . — Comptes Bendus , 
April 1st, 1877, p. 825. 
