[224] Goguet. i. p. 326.
[225] Plin. lib. xvi. c. 38, p. 32.
[226] Septalii Comm. in Aristotelis Problem. Lugd. 1632, fol. p. 206.
There is also a passage to the same purpose in Seneca, Epist. 108.
[227] See Anciennes Relations des Indes et de la Chine, de deux
voyageurs Mahometans, qui y allèrent dans le neuvième siècle. Par
Renaudot. Paris, 1718, 8vo, p. 25.
[228] Ars magna lucis et umbræ. Amst. 1671, fol. p. 102. Kircher
repeats this account with some new circumstances in his Phonurgia, p.
132.
[229] Morhofii Diss. de vitro per vocis sonum rupto, in
Dissertationibus Academicis. Hamburgi 1669, 4to, p. 381.
[230] Morhof quotes the following passage:--“With this brazen horn,
constructed with wonderful art, Alexander the Great called together
his army at the distance of sixty miles. On account of its inestimable
workmanship and monstrous size, it was under the management of sixty
men. Many kinds of sonorous metals were combined in the composition of
it.”
[231] “Among many things which the celebrated D’Alance caused to be
made for this purpose, the trumpet ascribed to Alexander, and with
which he called together his army, ought not to be omitted. As the
figure of it was represented in an old manuscript in the Vatican
library, and had been described by Bettini, that learned man was
desirous of trying whether it could be proved by experience, and the
attempt succeeded; for that kind of trumpet, if it does not excel,
seems undoubtedly to equal the other instruments constructed for that
end.”
[232] Bettini Apiaria univ. Philosophiæ Mathemat. Bonon. 1642, fol. p.
38.
[233] Magia Natural. lib. xx. c. 5.
[234] “To communicate anything to one’s friends by means of a tube.
This can be done with a tube made of earthenware, though one of lead is
better, or of any other substance, but very close, that the voice may
not be weakened; for whatever you speak at the one end, the words issue
perfect and entire as from the mouth of the speaker, and are conveyed
to the ears of the other, which, in my opinion, may be done for some
miles. The voice, neither broken nor dispersed, is carried entire to
the greatest distance. We tried it at the distance of two hundred
paces, not having convenience for a greater, and the words were heard
as clearly and distinctly as if they had come from the mouth of the
speaker.”--Lib. xvi. c. 12.
[235] Mathematische Erquickstunden, i. p. 243.
[236] An Account of the Speaking-trumpet, as it hath been contrived and
published by Sir Samuel Morland, knight and baronet, together with its
use both at sea and land. London, 1671. An extract from it may be seen
in the Phil. Trans., No. 78, p. 3056.
[237] Among the antiquities of Syracuse in Sicily, one beholds with
wonder chambers and galleries which are hewn out in the solid rock,
and particularly a grotto, from which arises a winding passage, that
becomes upwards still narrower. Ancient tradition says that this was a
prison, which the celebrated tyrant Dionysius caused to be built for
state prisoners, that in an apartment of his palace, which stood over
the narrow end of the passage, he might hear everything the prisoners
said, or what plots they formed against him. This grotto therefore
is called _Orechio di Dionysio_, or _la grotta della favella_; _auris
Dionysii_, the ear of Dionysius. Many travellers and others formerly
imagined that this passage was an ingenious imitation of that part of
the human ear called the helix, which was first remarked by Alcmaon
the Pythagorean. This is the account given by Kircher, who was there
in the year 1638. See his Phonurgia (published 1673), p. 82, where
there is a figure of it. In later times, however, this grotto has
been examined with more skill and acuteness by people less subject to
prejudice, and since that period the supposed wonder has been lessened.
The rock consists of limestone, at least I conclude so from what is
said by Brydone, who found it everywhere full of cracks and fissures.
The stones of which Syracuse was built were hewn from the rock; and
hence have been formed these chambers or openings, like those found in
the neighbourhood of other ancient and modern cities, such as Rome,
Naples, and Maestricht. Many of these, in the course of time, have been
employed as prisons, or used as burying-vaults. The above-mentioned
passage, which has excited so much wonder, is not properly spiral, and
is of such a figure that it may have been produced either by accident
or through the whim of the workmen employed to hew out the stones.
The double echo which Kircher assures us he heard in the grotto was
not remarked by Schott, who was there in 1646, as he expressly says,
in opposition to his brother jesuit, in his Magia Naturalis. In the
accounts still remaining of Dionysius we find mention of an astonishing
prison, which is well described by Cicero in his fifth oration against
Verres: “You have all heard of,” says he, “and most of you know the
prison (lautumias) of Syracuse. It is an immense and magnificent work,
executed by kings and tyrants; the whole is sunk to a wonderful depth
in the rock, and has been entirely cut out by the labour of many
hands. No place so secured against an escape; no place so enclosed
on all sides; no place so safe for confining prisoners can be either
planned out or constructed.” But it cannot be proved, and according to
D’Orville’s opinion it is improbable, that this grotto was the work of
that tyrant, who, as Plutarch tells us in his Life of Dion, employed
very different means to learn the intention of dangerous persons. “The
common people attacked the tyrant’s friends, and seized those whom they
called his emissaries (προσαγώγιδας), worthless men, detested by the
gods. These went about the city, mixed with the citizens, and, prying
into everything, gave an account to the tyrant of what they thought and
what expressions they made use of.” It was merely for its strength, and
the labour employed in building it, and not on account of its ingenious
construction, that the ancients admired the prison of the tyrant. At
present the upper end of the winding passage is closed up; and it is
so narrow, that some years ago the captain of an English vessel found
great difficulty to clamber up it. It cannot, however, be denied that
this grotto may have been used for the service ascribed to it; and I
can readily believe that it may have led Kircher to the invention of
the ear-trumpet. See the Travels of P. de la Valle, Ray, and Brydone;
Delle antiche Siracuse, da G. Bonanni, &c., 2 vols. fol. Palermo 1717.
Dan. Bartolo del suono e de’ tremori harmonici, Bonon. 1680, who
examined this grotto as a naturalist. D’Orville, Sicula. Amst. 1764,
pp. 182, 194.
[238] This machine was invented by Kircher, in imitation of the ear
of Dionysius; nor is it a vain and empty speculation, for the machine
produces an infallible effect. Kircher caused to be made at Rome, of
tin plate, a very large and straight tube, like a funnel, and placed it
in an apartment next to his chamber, in such a manner that the large
end projected into the garden of the college, and the less entered his
chamber. When the porter of the college had occasion to call him to the
gate, that he might not be obliged always to go up stairs, or to bawl
out, he went to the broad end of the funnel, and communicated what he
wished to Kircher.--Schotti Magia Universalis, ii. p. 156.
[239] Eschinardi Discursus de Sono Pneumatico, p. 10.
[240] Physico-theology.
[241] Our Kircher, in his Phonurgia, justly claims that invention,
as it was several years ago exhibited by him in the Jesuits’ college
at Rome, and an account of it printed. That this is true I myself
was an eye-witness; though I must acknowledge that no one before the
above-mentioned Englishman ever applied this speaking instrument, at
least in so perfect a manner, to that use for which it was afterwards
employed.--Magisterium Naturæ et Artis. Brixiæ, 1684-92, fol. ii.
p. 436.
[242] Journal des Sçavans, tome iii.
[243] Ibid. p. 131.
[244] J. A. Sturm, Collegium Experimentale, ii. p. 146.
[245] Philosophical Transactions.
[246] Mémoires de l’Acad. des Sciences à Berlin, 1763, p. 97.
[247] Experimental Inquiry into the Nature, &c. of Heat, p. 225.