The Key of Solomon is organised in a way that tells you what kind of book it is. The first book sets out the operations, a catalogue of what may be attempted and the conjurations for each; the second sets out the preparations, which is to say the far longer and more demanding business of ritual purity, timing, the making of instruments, and the consecration of everything used.
The proportion is the point. The conjurations are short. The preparations govern what the operator eats, when he bathes, what he wears, the phase of the Moon, the planetary hour, the virgin parchment, the knife with a white handle and the knife with a black one, the burin, the needle, the silk cloths, the water and the hyssop. This is a book about discipline in which the magic occupies a minority of the pages.
Its best known contents are the pentacles, circular figures for each planet combining Hebrew divine names and biblical verses, which are reproduced constantly in later occult publishing and which vary considerably between manuscripts. There is no single authoritative set, a fact usually lost when they are reprinted as though there were.
Manuscripts of the Key differ substantially from one another in contents, order and even in which spirits or angels are addressed, and there is no critical edition establishing an original. What most English readers know as the Key of Solomon is the version Mathers edited from British Museum manuscripts in 1889.