The first of Steiner's cosmic cycles, the "Old Saturn" era, is described as being a universe in which the densest substance is "heat" or "warmth". Here the Solar System was single mass, witrh the densest substance being "warmth"
What exactly Steiner means by this is contradictory. At times he says he is describing a spiritual warmth, which he also identifis with the Ego, e.g. if we say someone is a "warm person". Hence this is a purely spiritual state, equivalent to what I would refer to as the Inner Soul reality.
Yet at otehr times - e.g. when referring to the "Old Sun" condition, in which the densist substance is "air" or "gas", Steiner speaks of ball of fiery gas" i.e. the warmth principle and the air principle. This indictaes that the Warmth is of a material nature. This of course is absurd. As physical science points out, there is no actual substance called "heat"; temperature is simply the result of the motion or speed of vibration of atoms and other particles. The faster the particle vibrates, the "hotter" it is. According to Steiner though, "heat" is an actual substance, which stands in the same relation to gas as gas does to liquid.
The best we can say is that when Steiner is describing something in the previous cosmic stages as physical, he is actually referring to something which preceeds the physical, what I (and he also) terms the Etheric plane.
The following description of the "Saturn Metamorphosis" according to Steiner is by Paul E. Chu, from his book Life before Birth - Life on Earth, Life after Death. This is a very poorly written book, and the only reason I am quoting it is that it is easier to use an already-written summary than having to plough through Steiner's voluminous descriptions.
"The Creation of our solar system started as a spiritual activvity...In the beginning, from out of...the Zodiac, nine Hierarchies of Spiritual Beings were summoned from the realm of the Father God by God the Son to form a new hierarchy, Man." [Chu, p.86]
Note: This monotheistic approach is not usually charatristic of Steiner, who is more often an emanationist of sorts. It should be pointed out that Steiner usually identifieds Christ with one of the grades or hierrachies, which means that Christ is not the same as God the Son (and moreover Jesus is not the same as Christ). This is a similiar approach to the Christian Gnostics, with their numerous hypostases of Christ etc.
The highest two hierarchies, Seraphim and Cherabim, or Spirits of Love and Harmony, 'stand in the Presence of God' and interpret God the Son's intentions. The next highest hierarchy, the Thrones or Spirits of Will had reached a point of development where they were able to sacrifice of their substance, Will. This is of the nature of the warmth of soul such as is fired in the enthusiasm of a person today. This warmth is spiritual in nature and is invisible and not connected with substance, because there was no substance in our solar system at that time.
The warmth was worked on by the other hierarchies to form a spiritual beginning of the first rudiment of the physical bodily forces of man. Occult Science, i.e., that science hidden from the ordinary gaze of man, calls the development of the warmth sphere Ancient Saturn, or simply Saturn... [Chu, pp.86-7]
Central to Steiner's cosmology is the theory of Spiritual Hierarchies, or Demiurges as I prefer to call them. As in Greek (Platonic and pre-Platonic) and Hellenistic (Middle Platonic, Gnostic, Manichaean, etc) thought, the powerful - but not absolute or omnipotent - beings who fashioned the visible cosmos from the original Chaos. Of all the writers, it is Steiner who gives the clearest account of the workings of these powers. In his Cosmic Memory (one of his earliest esoteric works), he writes:
"These spirits are the creators of the man of Saturn. From their bodies they pour the substance which becomes the carrier of the human Saturn consciousness....(T)his takes place (during)...the first small Saturn cycle...The material body which man receives in this way is the first rudiment of his later physical body. One could say that the germ of the physical human body is planted during the first Saturn cycle by the Spirits of Will, and...this germ has the dull Saturn consciousness" [Cosmic Memory p.176]
For Steiner then, creation is not an external thing, a sort of fashioning, but rather a kind of outpouring; an emanation process. In a later and more definitive work, Occult Science, he gives a somewhat different account. He speaks of creation through a kind of incarnation of the higher beings within the Saturn-nature.
"Just as our earth is surrounded by...an atmosphere, so was it also on Saturn, only this "atmosphere" was of a spiritual character. It consisted of the [higher Spiritual] beings....Between the heat bodies of Saturn and these beings there was a constant reciprical action. The latter submerged the members of their being into the...heat bodies of Saturn, and, although there was no life in these heat bodies themselves, the life of the [spiritual] beings...was expressed in them. They might be compared to mirrors...(T)hrough its activity Saturn vitalised the surrounding space by reflect-ing back, like an echo, the life sent down to it..." [Occult Science, p.122]
This process continues through each of the seven epoches of the Saturn evolution. Steiner's demiurgii do not stand aloof, but rather actively participate in the process of creation, and through evolving the cosmos bring about a progression or transformation in their own nature. In keeping with his rigid cosmology, Steiner has the highest hierarchy active in the first epoch, the next highest in the next epoch, and so on. And with each era, these spiritual beings themselves ascend one level. So the Spirits of Wisdom of the Sun era are at exactly the same level as the Thrones of the Saturn era.
Each of these eras is, as with the Theosophical cosmology, divided into seven shorter periods, and often these in turn are also divided into seven further sub-periods.
"Saturn consisted in the beginning of nothing but the very first rudiments of humanity... Man existed at that time only in the first rudiments of his physical body. Ancient Saturn was simply composed of individual physical human bodies". (The Influence of Spiritual Beings Upon Man p.38)
During this period, all the terrestrial kingdoms - mineral, plant, animal, and human - are lumped into one, which Steiner calls "man". So we have a single terrestrial kingdom; which we can call "man-mineral", and which constutes the totality of the Saturn-sphere. The Thrones are here at the Demiurgic level - i.e. at the level of the Spirits of Form in the present Earth era.
"The development passes through seven stages, each succeeding stage worked on by the next lower hierarchy, the Spirits of Will, Motion, Wisdom, Form, Personality (Archai), Archangels and Angels. While working on this member of man's being, each hierarchy in the course of Saturn evolution advanced a step. On Saturn, the Archai go through their humanity stage or ego stage, with warmth as their densest form." [Chu, pp.87-88]
Thus throughout these various eras and epoches, both human and spiritual beings evolve in an extremely deterministic way, so that every entity must evolve one stage in every era; the whole thing proceeding like some sort of cosmic clock.
"Not all the beings in each hierarchy and man reach full development. There are those which fall behind. At the end of the Saturn evolution, the laggard human entities form the rudiments of the present animal kingdom." [Chu p.88]
For Steiner, all the other kingdoms proceed originally from Man. That is his own take on both cosmic and biological evolution. For a long time I thought this quite bizarre. Then I realised what he proposed was a modified version of the old myth of the cosmic man or primordial giant (Anthropos, Purusha, Adam Kadmon, Ymir, Hun Tun etc etc), from the various parts of whom the universe and all the beings and souls emerged. Steiner's mistake is that he fails to discriminate between this cosmic mythological anthropos and man the psycho-physical being. Such confusion of the various planes is a constant and chronic problem in Steiner's teachings.
The following diagram gives the various stages of emanation/evolution according to Steiner's cosmology:
/>=========> human // //====> animal-human // \\ //=> plant-human > =========> animal // \\ // mineral-human \\====> plant-animal \\ // \\ \\=> mineral-plant >=========> Plant \\ // \\===> mineral-plant \\ \>========> mineral
"Old Saturn" "Old Sun" "Old Moon" "Earth"
"Human consciousness was of a deep trance condition. His entity, however, was used by the hierarchies to express themselves in their creative activity. At the end of Saturn, the Spirits of Will (Thrones) gave the predisposition for the highest member of man, spirit man. A cosmic 'sleep' state (pralaya) follows in which all is united. For a fuller account, see Cosmic Memory, Chapter 14, or Occult Science." Chu p.88
What is referred to here is the "seed" of spirit man principle. The actual faculty itself is still to be developed in future evolutionary stages, according to Steiner.