Instruments by which the voice could be so strengthened as to be heard
at a much greater distance than would otherwise have been possible,
were known in the earliest ages; for of all musical instruments, wind
instruments were first invented, and their use in war to give the
signal of battle, we find mentioned in Job[224]. It had been remarked,
even in Pliny’s time, that the least touch of a beam of wood could be
heard when the ear was applied to the other end[225]. It was known
likewise that the larger trumpets emitted a louder and stronger sound.
The Grecians had a wind instrument with the bellowing noise of which
the people who were placed to guard the vineyards frightened away the
wild animals[226]. All these wind instruments however were little
in comparison with the monstrous trumpets of the ancient Chinese, a
kind of speaking-trumpets, or instruments by which words could not
only be heard at the greatest distance possible, but could be also
understood[227]. This invention belongs to the 17th century, though
some think that traces of it are to be found among the ancient Grecians.
Kircher, as far as I have been able to learn, was the first person who
made known, from a very ancient manuscript of Aristotle, De Secretis
ad Alexandrum Magnum, preserved in the Vatican, that Alexander had
a prodigious large horn with which he could assemble his army at
the distance of a hundred stadia, or eight Italian miles. It was,
according to the manuscript, five cubits in diameter; and Kircher,
who gives a figure of it, which he says he found in the manuscript,
thinks that, on account of its size, it must have been suspended
from a beam by a ring. This horn has by many been considered as the
oldest speaking-trumpet[228], but in my opinion without reason.
Aristotelis Secretum Secretorum ad Alexandrum Magnum I have never had
an opportunity to see. It appears to have been printed only once, and
is, like all the other works ascribed to that philosopher, extremely
scarce; for they have all had the fate of being little regarded after
it became the unanimous opinion of the learned that they were forged.
These works, however, are old; some of them indeed very old: and, if
some one would take the trouble to fix their antiquity, they might be
used with advantage on many occasions. Morhof had in his possession
the edition of that book published by Alexander Achillinus, a physician
at Bologna, in 1516, which is a Latin translation from the Arabic[229].
If we compare what is said there and by Kircher, we may make the
following conclusion:--
In the first place, it is certain that the book itself, as well as
the whole account, is not the production of Aristotle, for in all the
writers who relate the actions of Alexander we do not find the least
mention of such a horn. Secondly, it is not expressly said in that work
that Alexander spoke through this horn, but only that he assembled his
soldiers by it, which in past times was done by the sound of a trumpet,
and at present is done both by trumpets and drums. It appears also
that the author of the book, perhaps an Arabian, intended to give the
reader an idea of a horn that had an uncommonly strong and loud sound.
Thirdly, Kircher’s account and figure of the horn do not agree with
that which Morhof found in the edition of Achillinus[230]. Lastly,
none of these descriptions are such that an instrument to serve as a
speaking-trumpet could be constructed from them.
Wolf and other mathematicians are of opinion that the most advantageous
form of a speaking-trumpet would be found with more certainty by
experience than by theory. It may then be asked, whether any one ever
caused such an instrument to be made from these descriptions. Kircher,
who attempted things much more improbable, says he never tried it.
Duhamel however relates that a Frenchman tried it, and discovered
the real instrument[231]; but this information is of little weight,
as it is much to be doubted that this Frenchman caused it to be made
sufficiently exact according to the ancient description. I am as little
acquainted with Bettini as Morhof; but I suspect that Duhamel meant
Mar. Bettini, who, without making the smallest mention of Alexander’s
horn, proposes only a tube, the one end of which should be applied
to the mouth of a person who speaks, and the other to the ear of one
who is dull of hearing[232]. This was rather an ear-trumpet than a
speaking-trumpet, and it is certain that the former was invented before
the latter.
What we read in Porta, and what many think alludes to a
speaking-trumpet, alludes evidently to an ear-trumpet only. That author
infers, very justly, from the form of the ear, and particularly from
that of the ears of those animals which are quick of hearing, that to
hear at a distance one must apply to the ear a kind of wide funnel,
as people to strengthen the sight use spectacles[233]. He asserts
also, with equal truth, that one, through a long tube, can convey a
whisper to the ear of another person at a very great distance[234]; an
experiment which he himself made at the distance of two hundred paces.
Schwenter, who wrote before the speaking-trumpet was known, proposes,
from the hint of Porta, an ear-trumpet, one end of which should be
applied to the ear[235].
Sir Samuel Morland, an Englishman, and the jesuit Kircher, have in
later times contended respecting the invention of the speaking-trumpet.
The former, in 1671, published a particular description of one,
after he had made many experiments upon it the year preceding. This
instrument, shaped like a wide-mouthed trumpet, he caused first to
be constructed of glass, and afterwards of copper, with various
alterations, and performed several experiments with it in presence of
the king (Charles II.), prince Rupert, and other persons, who were
astonished at its effects[236].
As an account of this discovery was soon spread all over Europe,
Kircher asserted that he had constructed speaking-trumpets before
Sir Samuel Morland, and supported his assertion by referring to his
former writings, and by the testimony of other authors. I shall first
take notice of the former. His Ars Magna Lucis et Umbræ was first
printed in 1643. I at least conclude so, because, in the preface to his
Phonurgia, printed in 1673, he says that work had been published thirty
years before. The second edition is of 1671, in which I find only the
already-quoted passage respecting Alexander’s horn, and the figure of
a tube, which, like that proposed by Bettini, should be applied to
the ear of a person who hears, and to the mouth of the speaker. The
Musurgia, printed in 1650, contains better grounds for supporting the
assertion of Kircher. In the second part he describes how a funnel
can be placed in a building in such a manner, that a person in an
apartment where the narrow end is introduced can hear what is spoken
without the building, or in another apartment, where the wide end may
be. To this description a figure is added, and the author acknowledges
he was led to that idea by the construction of a well-known building
of Dionysius[237]. He does not however say expressly that he had
ever tried the experiment; but in the last page of the preface to the
Phonurgia, he pretends that so early as the year 1649 he had caused
such a machine to be fixed up in the Jesuits’ college. But, supposing
this to be true, it can only be said that he then approached very near
to the invention of the speaking-trumpet, by an instrument, which, in
reality, however, was calculated to strengthen the hearing, and not
the voice; and therefore only the half is true of what he advanced in
his preface in 1673, that twenty years before he had described in his
Musurgia the trumpet invented in England.
In the Phonurgia, however, written after Morland’s publication was
everywhere known, Kircher certainly treats of the speaking-trumpet,
and says that, from the similarity of the progress of sound to that
of the rays of light, he was led to the idea of conveying the former,
in the same manner as the latter, to a great distance, by means of
an instrument. For this purpose, about twenty-four years before, he
had caused to be constructed, in the Jesuits’ college at Rome, an
ear-trumpet, through which the porter could communicate anything he had
to say to him when he was in his apartment in the upper story. This
apparatus attracted the notice of many strangers, who were astonished
at its effect. He here represents it as a proper speaking-trumpet,
and adds, that it excited much surprise, on account of the uncommon
strength which it gave to the voice. For this reason he was very
desirous of trying to what distance words could be distinctly conveyed
by such a tube; and an opportunity occurred of doing this the same
year that he wrote his Phonurgia. From a convent, situated on the top
of a mountain, he assembled twelve hundred persons to divine service,
at the distance of from two to five Italian miles, and read the Litany
through it. Soon after, the emperor caused a tube to be made according
to Kircher’s description, by which, without elevating the voice, he
could be understood from Ebersdorf to Neugebeu. But though Kircher came
so near to the invention of the speaking-trumpet, it does not appear
certain by his works that he attempted or constructed it before Sir
Samuel Morland. I shall now examine the evidences he adduces in his
favour.
The most important of these is Schott, because he published his Magia
Naturalis[238] in 1657, before the invention of Sir Samuel Morland.
All that is to be found in this work, however, relates alone to the
ear-trumpet, a figure of which is added from the Musurgia; but we
learn, with certainty, that Kircher then had the before-mentioned
funnel or tube in his apartment. It is also not improbable that he
had tried to answer the porter from his apartment, and that he had
thereby remarked that the voice was strengthened; for it is not proved
by Schott that he at that time was acquainted with and had in his
possession a portable speaking-trumpet.
Another author by whom Kircher endeavours to support his claim is
Harsdorfer; who, however, speaks only of tubes to be closely applied
to the mouth and to the ear, and who refers to the Musurgia, without
mentioning the real speaking-trumpet, though the second part of his
Mathematical Recreations was first printed in 1677, and the third
in 1692. Besides these testimonies, Kircher quotes also Eschinard
concerning sound[239]. With that work I am not acquainted; but as the
information it contains is taken from the Musurgia, it is of as little
importance as that of Derham[240], who refuses the invention to his
countryman, and gives it to Kircher. When I unite all the evidence in
favour of Kircher, it appears to be certain that he made known and
employed the ear-trumpet earlier than the portable speaking-trumpet;
that he, however, approached very near to the invention of the latter,
but did not cause one to be constructed before Sir Samuel Morland, to
whom the honour belongs of having first brought it to that state as to
be of real use. Such, at least, is the manner in which this dispute is
decided by the Jesuit De Lanis[241].
When Morland’s invention was made known in France, it was pretended
that Salar, an Augustine monk, had seven or eight years before caused
such tubes or trumpets to be made, in order to strengthen the voice of
a weak bass-singer; but he himself acknowledges that he never had an
idea of speaking with them at a distance[242].
This instrument was soon made for sale at Nuremberg in Germany,
particularly by that well-known artist Grundler, mentioned by Becher,
who imagined that two persons, by means of a speaking-trumpet and an
ear-trumpet, could converse together at a great distance, without any
one in the neighbourhood, or in the intermediate space, hearing what
they said.
Of those who employed their ingenuity in improving this instrument
I shall mention the following. Cassegrain, known on account of
his optical instruments, published some hints for that purpose in
1672[243]; as did Sturm[244], Conyers[245], Hase and others afterwards.
The last who investigated the theory of the speaking-trumpet was
Lambert[246]; according to whose ideas the figure of a shortened
cone, if not the best, is at least as good as any other that might be
employed.
[It would appear, however, from the experiments of Hassenfratz (Journ.
de Phys., t. xxvi.) that neither the shape of the instrument nor the
material of which it is composed is of much consequence. He ascertained
the power of the trumpet by fixing a small watch in the mouth-piece,
and observing the distance at which the beats ceased to be audible,
and thus found that the effects were precisely the same with a trumpet
of tinned iron, whether used in its naked form, or tightly bound round
with linen to prevent vibration, or when lined with woollen cloth
whereby reflexion was entirely prevented; he also found that the range
of a cylindrical trumpet was as great as that of a conical one.
Leslie supposes the effect of the trumpet to be owing to the more
condensed and vigorous impulsion given to the air from its lateral
flow being checked. He observes, “that the tube, by its length and
narrowness, detains the efflux of air, and has the same effect as if
it diminished the volubility of that fluid, or increased its density.
The organs of articulation strike with concentrated force, and the
pulses, so vigorously thus excited, are, from the reflected form of the
aperture, finally enabled to escape and to spread themselves along the
atmosphere[247].”]