he sixteenth
and seventeenth centuries these doctrines of sympathies and antipathies
were much in vogue. A Scotchman, Sylvester Rattray, edited in the
"Theatrum Sympatheticum"(15) all the writings upon the sympathies and
antipathies of man with animal, vegetable and mineral substances, and
the whole art of physics was based on this principle.

(15) Rattray: Theatrum Sympatheticum, Norimberge, MDCLXII.

Upon this theory of "mumia," or magnetic force, the sympathetic cure of
disease was based. The weapon salve, the sympathetic ointment, and the
famous powder of sympathy were the instruments through which it acted.
The magnetic cure of wounds became the vogue. Van Helmont adopted these
views in his famous treatise "De Magnetica Vulnerum Curatione,"(16) in
which he asserted that cures were wrought through magnetic influence.
How close they came to modern views of wound infection may be judged
from the following: "Upon the solution of Unity in any part the ambient
air . . . repleted with various evaporations or aporrhoeas of mixt
bodies, especially such as are then suffering the act of putrefaction,
violently invadeth the part and thereupon impresseth an exotic miasm or
noxious diathesis, which disposeth the blood successively arriving at
the wound, to putrefaction, by the intervention of fermentation." With
his magnetic sympathy, Van Helmont expressed clearly the doctrine of
immunity and the cure of disease by immune sera: "For he who has once
recovered from that disease hath not only obtained a pure balsaamical
blood, whereby for the future he is rendered free from any recidivation
of the same evil, but also infallibly cures the same affection in his
neighbour . . . and by the mysterious power of Magnetism transplants
that balsaam and conserving quality into the blood of another." He was
rash enough to go further and say that the cures effected by the relics
of the saints were also due to the same cause--a statement which led to
a great discussion with the theologians and to Van Helmont's arrest for
heresy, and small wonder, when he makes such bold statements as "Let the
Divine enquire only concerning God, the Naturalist concerning Nature,"
and "God in the production of miracles does for the most part walk hand
in hand with Nature."

(16) An English translation by Walter Charleton appeared in 1650,
entitled "A Ternary of Paradoxes."

That wandering genius, Sir Kenelm Digby, did much to popularize this
m