1. The document discusses the historical beliefs in the talismanic and magical properties attributed to agate gemstones, such as bringing good fortune, protection from harm, and helping persuade others. 2. It describes past theories on how agate amulets could provide benefits like curing insomnia or ensuring pleasant dreams, and how some scholars like Cardano tested the effects of gemstones by wearing them and monitoring the results. 3. The text also mentions an 1709 proposed design for an airship that was intended to harness the supposed magnetic powers of coral agates to help lift the craft into the air.

1. On the Talismanic Use of Special Stones36
[ SpeciFics-Data Acquisition@ www.Google.com ].
Agate
THE author of “Lithica” celebrates the merits of the agate in
the following lines:37
Adorned with this, thou woman’s heart shall gain,
And by persuasion thy desire obtain;
And if of men thou aught demand, shalt come
With all thy wish fulfilled rejoicing home.
This idea is elaborated by Marbodus, Bishop of Rennes, in
the eleventh century,who declares thatagates make the wearers
agreeable and persuasive and also give them the favor of
God.38
Still other virtues are recounted by Camillo Leonardo,
who claims that these stones give victory and strength to their
owners and avert tempests and lightning.39
The agate possessed some wonderful virtues, for its wearer
was guarded from all dangers, was enabled to vanquish all
terrestrial obstacles and was endowed with a bold heart; this
latter prerogative was presumably the52 secret of his success.
Some of these wonder-working agates were black with white
veins, while others again were entirely white.40
The wearing of agate ornaments was even believed to be a
cure for insomnia and was thought to insure pleasant dreams.
In spite of these supposed advantages, Cardano asserts that
while wearing this stone he had many misfortunes which he
could not trace to any fault or error of his own. He, therefore,
abandoned its use; although he states that it made the wearer
more prudent in his actions.41
Indeed, Cardano appears to have
tested the talismanic worth of gems according to a plan of his

2. own,—namely, by wearing them in turn and noting the degree
of good or ill fortune he experienced. By this method he
apparently arrived at positive results based on actual
experience; but he quite failed to appreciate the fact that no real
connection of any kind existed between the stones and their
supposed effects. In another treatise this author takes a
somewhat more favorable view of the agate, and proclaims that
all varieties render those who wear them “temperate,continent,
and cautious; therefore they are all useful for acquiring
riches.”42
According to the text accompanying a curious print published
in Vienna in 1709, the attractivequalities of the so-called coral-
agate were to be utilized in an air-ship, the invention of a
Brazilian priest.
Over the head of the aviator, as he sat in the air-ship, there
was a network of iron to which large coral-agates were
attached.53These were expectedto help in drawing up the ship,
when, through the heat of the sun’s rays, the stones had
acquired magnetic power. The main lifting force was provided
by powerful magnets enclosed in two metal spheres; how the
magnets themselves were to be raised is not explained.43

3. AN AIR-SHIP OF 1709.
In the network above the figure were to be set coral-
agates, supposed to possess such magnetic powers as to keep
the craft aloft. From Valentini, “Museum Museorum,” Pt.
III, Franckfurt am Mayn, 1714, p.35. Author’s library.
In the network above the figure were to be set coral-agates,
supposed to possess such magnetic powers as to keep the craft
aloft. From Valentini, “MuseumMuseorum,” Pt.III, Franckfurt
am Mayn, 1714, p.35. Author’s library.]
54
About the middle of the past century, the demand for agate
amulets was so great in the Soudan that the extensive agate-
cutting establishments at Idar and Oberstein in Germany
were almost exclusively busied with filling orders for this trade.

4. Brown or black agates having a white ring in the centre were
chiefly used for the fabrication of these amulets, the white ring
being regarded as a symbol of the eye. Hence the amulets were
supposed to neutralize the power of the Evil Eye, or else to
be emblematic of the watchfulness of a guardian spirit.
The demand for these amulets has fallen off greatly, but when
it was at its height single firms exported them to the value of
40,000 thalers ($30,000) annually, the total export amounting
to hundreds of thousands of thalers.
Even at present a considerable trade in these objects is still
carried on. That there is a fashion in amulets is shown by the
fact that, while red, white, and green amulets are in demand on
the west coast of Africa, only white stones are favored for this
use in Northern Africa.
****************************************************************