Evolution and Devolution of the Elements, 37 
under certain conditions ; at the same time, these rings 
should have extraordinary properties inasmuch as we can 
only view the evolution from manganese as being in the 
nature of plastering up its ring, so to speak. For these 
reasons, as well as from the facts of stellar evolution, we 
consider that iron, nickel, and cobalt are the products of this 
operation. Now the properties of the external rings of these 
elements are certainly very abnormal. These three elements 
are strongly magnetic and so we may look upon their rings 
as being to a certain extent plastic ; that is to say, they are 
readily deformed under the influence of a magnetic field. 
It is perfectly true that none of these three elements shows 
the expected valency of eight, but in the elements ruthenium 
and osmium, which are the direct derivatives of iron, we do 
find evidences of this octo-valency. We would argue from 
this that the octovalent character is latent in the case of iron 
<fcc, that it becomes more pronounced in the case of ruthenium, 
which gives a tetroxide known in combination, and still more 
pronounced in the case of osmium, which gives a perfectly 
stable tetroxide. 
It must be pointed out here that there is a very considerable 
difference between the octovalent ring of these elements and 
the saturated eight-membered ring of the elements belonging 
to the helium family. In the first case, we have a ring which 
can under suitable conditions give up eight electrons, but 
which prefers to act by secondary valencies, especially the 
valencies of two, three, and four. On the other hand, the 
rings of the elements of the helium family must be looked 
upon as saturated rings which have no power to act by 
secondary valencies at all. 
There is no doubt that the elements iron, nickel, cobalt, and 
other direct evolution products represent a somewhat unsatis- 
factory condition of affairs, and that each one of them will 
tend in the natural course of evolution to recover itself 
and form more or less ordinary derivatives. We think that 
the elements copper, zinc, gallium, and germanium, and the 
elements directly below them, represent these recovery 
products. That is to say, copper, zinc, gallium, and ger- 
manium are the successive recovery products of iron, nickel, 
and cobalt, while silver, cadmium, indium, and tin are 
the successive recovery products of ruthenium, rhodium, 
and palladium, and that gold, mercury, thallium, and 
lead are the successive recovery products from osmium, 
iridium, and platinum. We will return to this question of 
recovery again when dealing with the electropotential series 
of Professor Abegg. 
