which the other systems are in use; and
others cannot be understood by persons
possessing ordinary eyesight.

Some years ago, David Macbeath, a blind
teacher in the Edinburgh Blind Asylum,
invented an ingenious String Alphabet. It
consists of a cord on which knots are tied,
the knots having differences in shape, size,
and position, sufficient to indicate different
alphabetic or verbal sounds. One knot is
round, another the drummer's plait, a third
the simple noose, a fourth the net knot,
a fifth the twisted noose, and so on. The
knotted cord is wound upon a vertical frame,
which revolves and passes from the reader as
he proceeds. Considerable portions of the
New Testament have been set up (to use a
printer's phrase) in this manner. The pupil
reads by feeling the knots upon the string;
but the process is necessarily very slow.

One of the earliest inventions for teaching
the Blind to read consisted of moveable
wooden letters, placed on small wooden
tablets grooved to receive them, on a principle
similar to that adopted in some children's
toys. It is said that by such a method
Archbishop Usher was taught to read by two
relations who were both blind. Moveable
leaden letters were afterwards cast for this
purpose, by Moreau of Paris.

Mr. Gibson of Birmingham has invented an
ingenious mode of enabling the Blind to write
and to keep accounts. Every letter or figure is
represented by a small cube of wood or other
soft material, with a type on its upper surface,
and a similar type on its under surface
formed of needle-points. If a piece of paper
be laid on a cushion, and the cube be pressed
upon it, the needle-points will make impressions
which can be felt in relief on the other
side of the paper. If two or three sheets of
paper be placed on the cushion, two or three
copies of the same entry may be obtained at
once. The type on the upper surface of each
little cube guides the pupil in his selection;
while the needle-point type at the lower
surface produces the record or impression.
Mr. Gibson also devised an apparatus for
working arithmetic. It consists of a flat
surface divided into rows by elevated slips of
wood, along which the types are made to
slide. These types have no needle-points
on the under surface, the process being for
temporary working and not for permanent record.

The French have largely used a plan of
Dr. Guillié's for teaching geography by relief
maps. The map of a country is pasted upon
thick pasteboard; a wire is bent round the
curves of the coast, and along the courses of
the rivers; these wires are fastened down,
and a second map, in every respect similar to
the first, is pasted over it; when this is
pressed, the windings of the wire will be
easily traced by the touch. An American
improvement has been made on this system,
by having a metal plate engraved with all
the lines, elevations, boundaries, positions of
towns, &c. From this plate impressions are
struck in pasteboard, which produce an
embossed map. Some of the excellent German
relief maps, made for the illustration of
physical geography, have also been rendered
available for teaching the Blind; and an
obvious extension of the same system has
been made to the production of orreries,
planetariums, and maps of the heavens.

Perhaps the best opportunity ever afforded
for studying and comparing these and similar
ingenious contrivances was at the Great
Exhibition in one thousand eight hundred
and fifty-one. Mr. Hughes, governor of
the Blind Asylum at Manchester, exhibited a
portable typograph to enable persons who
can read the common embossed letters, to
communicate one with another. The paper
to be written upon is placed within a
portfolio, one side of which is made of semi-
carbonized paper, as a humble substitute for an
inking-roller. This paper is beneath a sort of
graduated circle; the pupil turns an index hand
to any required letter (which he can easily feel);
and, by a slight pressure brings down a
type upon the paper, which thereby acquires
a slight blackened mark on the other surface
sufficiently distinct to be read. The embossing
produced enables the writing to be read
by blind readers, while the blackening renders
it readable by all who can see. There is a
very simple mechanism by which letters are
printed in proper order in a line, and the lines
in proper order in a page. It has been pointed
out that a blind person might usefully print
labels for museums, &c., by this apparatus.

Those who remember the French department
at the Exhibition, will call to mind a
blind man who, surrounded by sympathising
visitors, printed his thoughts on slips of
paper, which were distributed to those
interested in them. This was M. Foucault, the
inventor of the instrument by which the
result was produced. The instrument is very
remarkable. It contains about thirty vertical
brass rods, ranged in two rows. At the top
of each rod is engraved, in bold relief, a letter
of the alphabet, or a grammatical stop or
sign; and at the bottom is a corresponding
character formed of ordinary type. A piece
of blackened paper, with white paper beneath
it, is placed underneath the rods; and, on
the pressure of any rod, a black type-printed
mark appears on the white paper. Ingenious
mechanism enables the blind printer to
arrange letters and words in symmetrical lines.

Mr. Thompson, of the United States, produced
an instrument for teaching the Blind geography,
writing, drawing, and mathematics.
There is a tablet covered with
white leather, capable of yielding to the
pressure of a style without retaining the impression;
the style employed may be made of
any hard material capable of receiving and
retaining a rounded smooth point. A sheet
of paper is laid upon the leathern tablet; the
writing, or figures, or diagrams, are marked