Chapter I: Front Matter

LETTERS

ON

NATURAL MAGIC,

ADDRESSED TO

SIR WALTER SCOTT, BART.

BY

SIR DAVID BREWSTER, LL.D., F.R.S.

SEVENTH EDITION.

LONDON:
WILLIAM TEGG AND Co., 85, QUEEN STREET.
CHEAPSIDE.
1856.

CONTENTS.

LETTER I.

Extent and interest of the subject--Science employed by
ancient governments to deceive and enslave their subjects--Influence
of the supernatural upon ignorant minds--Means
employed by the ancient magicians to establish
their authority--Derived from a knowledge of the phenomena
of Nature--From the influence of narcotic drugs
upon the victims of their delusion--From every branch of
science--Acoustics--Hydrostatics--Mechanics--Optics--M.
Salverte’s work on the occult sciences--Object of
the following letters Page 1

LETTER II.

The eye the most important of our organs--Popular description
of it--The eye is the most fertile source of mental
illusions--Disappearance of objects when their images fall
upon the base of the optic nerve--Disappearance of objects
when seen obliquely--Deceptions arising from viewing
objects in a faint light--Luminous figures created by
pressure on the eye, either from external causes or from
the fulness of the blood-vessels--Ocular spectra or accidental
colours--Remarkable effects produced by intense
light--Influence of the imagination in viewing these
spectra--Remarkable illusion produced by this affection
of the eye--Duration of impressions of light on the
eye--Thaumatrope--Improvements upon it suggested--Disappearance
of halves of objects or of one of two persons--Insensibility
of the eye to particular colours--Remarkable
optical illusion described 8

LETTER III.

Subject of spectral illusions--Recent and interesting case
of Mrs. A.--Her first illusion affecting the ear--Spectral
apparition of her husband--Spectral apparition of a cat--Apparition
of a near and living relation in grave-clothes,
seen in a looking-glass--Other illusions, affecting
the ear--Spectre of a deceased friend sitting in an
easy-chair--Spectre of a coach-and-four filled with
skeletons--Accuracy and value of the preceding cases--State of
health under which they arose--Spectral apparitions are
pictures on the retina--The ideas of memory and imagination
are also pictures on the retina--General views of
the subject--Approximate explanation of spectral apparitions 37

LETTER IV.

Science used as an instrument of imposture--Deceptions
with plane and concave mirrors practised by the ancients--The
magician’s mirror--Effects of concave mirrors--Aërial
images--Images on smoke--Combination of
mirrors for producing pictures from living objects--The
mysterious dagger--Ancient miracles with concave
mirrors--Modern necromancy with them, as seen by Cellini--Description
and effects of the magic lantern--Improvements
upon it--Phantasmagoric exhibitions of
Philipstall and others--Dr. Young’s arrangement of
lenses, &c., for the Phantasmagoria--Improvements
suggested--Catadioptrical phantasmagoria for producing
the pictures from living objects--Method of cutting off
parts of the figures--Kircher’s mysterious hand-writing on
the wall--His hollow cylindrical mirror for aërial images--Cylindrical
mirror for re-forming distorted pictures--Mirrors
of variable curvature for producing caricatures 56

LETTER V.

Miscellaneous optical illusions--Conversions of cameos into
intaglios, or elevations into depressions, and the
reverse--Explanation of this class of deceptions--Singular
effects of illumination with light of one simple colour--Lamps
for producing homogeneous yellow light--Methods
of increasing the effects of this exhibition--Method of
reading the inscription of coins in the dark--Art of
deciphering the effaced inscription of coins--Explanation
of these singular effects--Apparent motion of the eyes
in portraits--Remarkable examples of this--Apparent
motion of the features of a portrait, when the eyes are
made to move--Remarkable experiment of breathing
light and darkness 98

LETTER VI.

Natural phenomena marked with the marvellous--Spectre
of the Brocken described--Analogous phenomena--Aërial
spectres seen in Cumberland--Fata Morgana in
the Straits of Messina--Objects below the horizon raised
and magnified by refraction--Singular example seen at
Hastings--Dover Castle seen through the hill on which it
stands--Erect and inverted images of distant ships seen
in the air--Similar phenomena seen in the Arctic regions--Enchanted
coast--Mr. Scoresby recognizes his father’s
ship by its aërial image--Images of cows seen in the air--Inverted
images of horses seen in South America--Lateral
images produced by refraction--Aërial spectres
by reflexion--Explanation of the preceding phenomena 127

LETTER VII.

Illusions depending on the ear--Practised by the ancients--Speaking
and singing heads of the ancients--Exhibition
of the Invisible Girl described and explained--Illusions
arising from the difficulty of determining the direction
of sounds--Singular example of this illusion--Nature of
ventriloquism--Exhibitions of some of the most celebrated
ventriloquists--M. St. Gille--Louis Brabant--M.
Alexandre--Capt. Lyon’s account of Esquimaux ventriloquists 157
LETTER VIII.

Musical and harmonic sounds explained--Power of breaking
glasses with the voice--Musical sounds from the
vibration of a column of air--and of solid
bodies--Kaleidophone--Singular acoustic figures produced on
sand laid on vibrating plates of glass--and on stretched
membranes--Vibration of flat rulers and cylinders of
glass--Production of silence from two sounds--Production
of darkness from two lights--Explanation of these
singular effects--Acoustic automaton--Droz’s bleating
sheep--Maillardet’s singing-bird--Vaucanson’s flute-player--His
pipe and tabor-player--Baron Kempelen’s
talking-engine--Kratzenstein’s speaking-machine--Mr.
Willis’s researches 179

LETTER IX.

Singular effects in nature depending on sound--Permanent
character of speech--Influence of great elevations on the
character of sounds, and on the powers of speech--Power
of sound in throwing down buildings--Dog killed
by sound--Sounds greatly changed under particular circumstances--Great
audibility of sounds during the night
explained--Sounds deadened in media of different
densities--Illustrated in the case of a glass of champagne--and
in that of new-fallen snow--Remarkable echoes--Reverberations
of thunder--Subterranean noises--Remarkable
one at the Solfaterra--Echo at the Menai suspension
bridge--Temporary deafness produced in diving-bells--Inaudibility
of particular sounds to particular ears--Vocal
powers of the statue of Memnon--Sounds in
granite rocks--Musical mountain of El-Nakous 212

LETTER X.

Mechanical inventions of the ancients few in number--Ancient
and modern feats of strength--Feats of Eckeberg
particularly described--General explanation of them--Real
feats of strength performed by Thomas Topham--Remarkable
power of lifting heavy persons when the
lungs are inflated--Belzoni’s feat of sustaining pyramids
of men--Deception of walking along the ceiling in an
inverted position--Pneumatic apparatus in the foot of
the house-fly for enabling it to walk in opposition to
gravity--Description of the analogous apparatus employed
by the gecko lizard for the same purpose--Apparatus used
by the Echineis remora, or sucking-fish 244

LETTER XI.

Mechanical automata of the ancients--Moving tripods--Automata
of Dædalus--Wooden pigeon of Archytas--Automatic
clock of Charlemagne--Automata made by
Turrianus for Charles V.--Camus’s automatic carriage
made for Louis XIV.--Degenne’s mechanical peacock--Vaucanson’s
duck which ate and digested its food--Du
Moulin’s automata--Baron Kempelen’s automaton chess-player--Drawing
and writing automata--Maillardet’s
conjurer--Benefits derived from the passion for automata--Examples
of wonderful machinery for useful purposes--Duncan’s
tambouring machinery--Watt’s statue-turning
machinery--Babbage’s calculating machinery 264

LETTER XII.

Wonders of chemistry--Origin, progress, and objects of
alchemy--Art of breathing fire--Employed by Barchochebas,
Eunus, &c.--Modern method--Art of walking
upon burning coals and red-hot iron, and of plunging the
hands in melted lead and boiling water--Singular property
of boiling tar--Workmen plunge their hands in
melted copper--Trial of ordeal by fire--Aldini’s incombustible
dresses--Examples of their wonderful power in
resisting flame--Power of breathing and enduring air of
high temperatures--Experiments made by Sir Joseph
Banks, Sir Charles Blagden, and Mr. Chantrey 227

LETTER XIII.

Spontaneous combustion--In the absorption of air by
powdered charcoal--and of hydrogen by spongy platinum--Dobereiner’s
lamp--Spontaneous combustion in the
bowels of the earth--Burning cliffs--Burning soil--Combustion
without flame--Spontaneous combustion of human
beings--Countess Zangari--Grace Pett--Natural fire-temples
of the Guebres--Spontaneous fires in the Caspian
Sea--Springs of inflammable gas near Glasgow--Natural
light-house of Maracaybo--New elastic fluids in the
cavities--of gems--Chemical operations going on in their
cavities--Explosions produced in them by heat--Remarkable
changes of colour from chemical causes--Effects
of the nitrous oxide or Paradise gas when
breathed--Remarkable cases described--Conclusion 313

LETTERS

ON

NATURAL MAGIC;

ADDRESSED TO

SIR WALTER SCOTT, BART.