TIN (Plate XVI, 3, 4).

Here we have only the spike to consider, as the funnels are the same as in germanium, and the central globe is that of t.i.tanium, omitting the eight atomed centre. The cone of the spike we have had in silver (see p. 729, May), and it is set free on the proto level. The spike, as in zinc, becomes a large sphere, with the single septet in the centre, the remaining six bodies circling round it on differing planes. They break up as shown. (Tin is Sn.)

IRON (Plate IV, I, and XVII, 3).

[Ill.u.s.tration]

We have already dealt with the affinities of this peculiar group, and we shall see, in the disintegration, even more clearly, the close relationships which exist according to the cla.s.sification which we here follow.

The fourteen bars of iron break asunder on the proto level, and each sets free its contents--a cone and three ovoids, which as usual, become spheres.

The twenty-eight-atomed cone becomes a four-sided figure, and the ovoids show crystalline contents. They break up, on the meta level as shown in the diagram, and are all reduced to triplets and duads on the hyper level.

COBALT (Plate XVII, 4).

The ovoids in cobalt are identical with those of iron; the higher ovoids, which replace the cone of iron, show persistently the crystalline forms so noticeable throughout this group.

NICKEL (Plate XVII, 5).

The two additional atoms in a bar, which alone separate nickel from cobalt, are seen in the upper sphere of the central ovoid.

RUTHENIUM (Plate XVIII, 1).

The lower ovoids in ruthenium are identical in composition, with those of iron, cobalt and nickel and may be studied under Iron. The upper ones only differ by the addition of a triplet.

RHODIUM (Plate XVIII, 2).

Rhodium has a septet, which is to be seen in the _c_ of t.i.tanium (see _k_ in the t.i.tanium diagram) and differs only in this from its group.

PALLADIUM (Plate XVIII, 3).

In palladium this septet appears as the upper sphere in every ovoid of the upper ring.

OSMIUM (Plate XVIII, 4).

We have here no new const.i.tuents; the ovoids are set free on the proto level and the contained globes on the meta, all being of familiar forms.

The cigars, as usual, break free on the proto level, and leave their ovoid with only four contained spheres, which unite into two nine-atomed bodies as in silicon (see above).

IRIDIUM (Plate XVIII, 5.)

The twenty-one-atomed cone of silver here reappears, and its proceedings may be followed under that metal (see diagram, p. 729, May). The remaining bodies call for no remark.

PLATINUM (Plate XVIII, 6).

Again the silver cone is with us. The remaining bodies are set free on the proto level, and their contained spheres on the meta.

LITHIUM (Plate IV, 2, and XIX, 1).

[Ill.u.s.tration]

Here we have some new combinations, which recur persistently in its allies.

The bodies _a_, in Plate XIX, 1, are at the top and bottom of the ellipse; they come to right and left of it in the proto state, and each makes a twelve-atomed body on the meta level.

The five bodies within the ellipse, three monads and two s.e.xtets, show two which we have had before: _d_, which behaves like the quintet and quartet in silicon, after their junction, and _b_, which we have had in iron. The two bodies _c_ are a variant of the square-based pyramid, one atom at the apex, and two at each of the other angles. The globe, _e_, is a new form, the four tetrahedra of the proto level making a single twelve-atomed one on the meta. The body _a_ splits up into triplets on the hyper; _b_ and _d_ follow their iron and silicon models; _c_ yields four duads and a unit; _e_ breaks into four quartets.

POTa.s.sIUM (Plate XIX, 2).

Pota.s.sium repeats the lithium spike; the central globe shows the "nitrogen balloon," which we already know, and which is surrounded on the proto level with six tetrahedra, which are set free on the meta and behave as in cobalt. Hence we have nothing new.

RUBIDIUM (Plate XIX, 3).

Again the lithium spike, modified slightly by the introduction of an ovoid, in place of the top sphere; the forms here are somewhat unusual, and the triangles of the s.e.xtet revolve round each other on the meta level; all the triads break up on the hyper level into duads and units.

FLUORINE (Plate IV, 3, and Plate XVII, 1).

The reversed funnels of fluorine split asunder on the proto level, and are set free, the "balloons" also floating off independently. The funnels, as usual, become spheres, and on the meta level set free their contained bodies, three quartets and a triplet from each of the eight. The balloons disintegrate in the usual way.

MANGANESE (Plate XVII, 2).

Manganese offers us nothing new, being composed of "lithium spikes" and "nitrogen balloons."

X.

VI.--THE STAR GROUPS.

We have now reached the last of the groups as arranged on Sir William Crookes' lemniscates, that forming the "neutral" column; it is headed by helium, which is _sui generis_. The remainder are in the form of a flat star (see Plate IV, 4), with a centre formed of five intersecting and "cigar"-bearing tetrahedra, and six radiating arms. Ten of these have been observed, five pairs in which the second member differs but slightly from the first; they are: Neon, Meta-neon; Argon, Metargon; Krypton, Meta-krypton; Xenon, Meta-xenon; Kalon, Meta-kalon; the last pair and the meta forms are not yet discovered by chemists. These all show the presence of a periodic law; taking an arm of the star in each of the five pairs, we find the number of atoms to be as follows :--

40 99 224 363 489 47 106 231 370 496 It will be observed that the meta form in each case shows seven more atoms than its fellow.

[Ill.u.s.tration: PLATE XX.]

HELIUM (Plate III, 5, and Plate XX, 1) shows two "cigar"-bearing tetrahedra, and two hydrogen triangles, the tetrahedra revolving round an egg-shaped central body, and the triangles spinning on their own axes while performing a similar revolution. The whole has an attractively airy appearance, as of a fairy element.

HELIUM: Two tetrahedra of 24 atoms 48 Two triangles of 9 atoms 18 Central egg 6 ---- Total 72 ---- Atomic weight 3.94 Number weight 72/18 4.00 NEON (Plate XX, 2 and 6) has six arms of the pattern shown in 2, radiating from the central globe.

NEON: Six arms of 40 atoms 240 Central tetrahedra 120

---- Total 360 ---- Atomic weight 19.90 Number weight 360/18 20.00 META-NEON (Plate XX, 3 and 6) differs from its comrade by the insertion of an additional atom in each of the groups included in the second body within its arm, and subst.i.tuting a seven-atomed group for one of the triplets in neon.

META-NEON: Six arms of 47 atoms 282 Central tetrahedra 120 ---- Total 402 ---- Atomic weight ---- Number weight 402/18 22.33 ARGON (Plate XX, 4, 6 and 7) shows within its arms the _b_ 63 which we met in nitrogen, yttrium, vanadium and niobium, but not the "balloon," which we shall find with it in krypton and its congeners.

ARGON: Six arms of 99 atoms 594 Central tetrahedra 120 ---- Total 714 ---- Atomic weight 39.60 Number weight 714/18 39.66 METARGON (Plate XX, 5, 6 and 7) again shows only an additional seven atoms in each arm.

METARGON: Six arms of 106 atoms 636 Central tetrahedra 120 ---- Total 756 ---- Atomic weight ---- Number weight 756/18 42 [Ill.u.s.tration: PLATE XXI.]

KRYPTON (Plate XXI, 1 and 4, and Plate XX, 6 and 7) contains the nitrogen "balloon," elongated by its juxtaposition to _b_ 63. The central tetrahedra appear as usual.

KRYPTON: Six arms of 224 atoms 1344 Central tetrahedra 120 ----- Total 1464 ----- Atomic weight 81.20 Number weight 1464/18 81.33 META-KRYPTON differs only from krypton by the subst.i.tution of _z_ for _y_ in each arm of the star.