1. _Hyle_[341] is the name the Greeks apply to the first material of things, which is in no way formed, but has a capacity for all bodily forms, and out of it these visible elements are shaped. Wherefore they have derived their name from this source.[342] This _hyle_ the Latins called _materia_, for the reason that everything in the rough from which something is made, is always called _materia_....

2. The Greeks moreover call the elements στοιχεῖα,[343] because they are akin to one another in the harmony of like quality and a sort of common character, for they are said to be allied with one another in a natural way, now tracing their origin from fire all the way to earth, now from earth all the way to fire, so that fire fades into air, air is thickened to water, water coarsened to earth, and again earth is dissolved into water, water refined into air, air rarefied into fire.

An encyclopedist of the dark ages: Isidore of Seville — Part 164

[343] The word στοιχεῖον means “one in a series.”

An encyclopedist of the dark ages: Isidore of Seville — Part 164

3. Wherefore all elements are present in all, but each of them has received its name from that which it has in greater degree. And they have been assigned by divine providence to the living creatures that are suited to them, for the Creator himself filled the heaven with angels, the air with birds, the sea with fish, the earth with men and other living creatures.

An encyclopedist of the dark ages: Isidore of Seville — Part 164

1. Ether is the place in which the stars are, and it signifies that fire which is separated on high from the whole universe. Ether is the element itself; and _aethra_ is the glow of the ether and is a Greek word.

1. Air is emptiness, having more rarity mixed with it than the other elements. Of it Virgil says:

Air (_aer_) is so called from αἴρειν (to raise), because it supports the earth or, it may be, is supported by it. This belongs partly to the substance of heaven, partly to that of the earth. For yonder thin air where windy and gusty blasts cannot come into existence, belongs to the heavenly part; but this more disordered air which takes a corporeal character because of dank exhalations, is assigned to earth, and it has many subdivisions: for being set in motion it makes winds; and being vigorously agitated, lightnings and thunderings; being contracted, clouds; being thickened, rain; when the clouds freeze, snow; when thick clouds freeze in a more disordered way, hail; being spread abroad, it causes fine weather; for it is known that thick air is a cloud and that a cloud that thins and melts away, is air.