CHAPTER IV.

Concerning the Properties of Fire.
After you have placed the matter in the proper vessels, you will cherish it with natural heat, so that the outside shall not exceed the inside. For if the heat be excessive, no conjunction will take place, because by the intense heat the matter is dispersed and burnt, so that no advantage arises from it. On this account the mid region of the air has been arranged by Nature between heaven and earth ; otherwise the sun and the stars would burn up all the creatures on the earth, so that nothing could be produced from it. Take care, therefore, that between the matter and the fire you interpose an airy part of this kind, or a certain distance. In this way the heat will not easily be able in any way to do injury, nor to disperse, and still less to burn. For if the heat be insufficient neither will the spirit rest acting in no way upon
Concerning the Spirits of the Planets,
83
lis. own humidity j so it will be dried or fixed. For the spirits of metals are of themselves dead» and resti and can effect nothing unless they are vitalised* None otherwise in the great world the seed cast into the earth is dead, and cannot grow of itself unless it be vitalised by the heat of the sun. In the very first place, therefore, is it necessary to buiJd the fire for this work In just proportion, neither too large nor too small ; otherwise this work will never be carried on to its desired and perfect end.