The Hand of the Philosophs

"This is the hand of the philosophers with their seven secret signs, to which the ancient sages were bound.

The thumb:  Just as the thumb powerfully closes the hand, so does saltpetre do in art.

The index finger:  Next to saltpetre, vitriol is the strongest salt.  It penetrates all metals.

The middle finger: Sal ammoniac shines through all metals.

The ring or gold finger: Alum gleams through the metals. It has a wonderful nature and the most subtle Spiritus.

The ear finger: Common salt is the key to art.

The palm: The fish is Mercury, the fire Sulphur. "

J.I.Hollandus, Chymische Schriften, Vienna, 1773