lmar, 1809.

Weissemburgh, of Mannheim, became blind at the age of seven years. He
wrote perfectly, and read with characters which he had imagined for his
own use. He was an excellent geographer, and composed maps and globes,
which he employed both in studying and teaching this science. He was the
inventor of an arithmetical table differing but little from that of
Sanderson.

An Extraordinary Questioner.

The blind man of Puiseaux must be known to all who read Diderot's
celebrated "Lettres sur les Aveugles." He was the son of a professor of
philosophy in the University of Paris, and had attended with advantage
courses of chemistry and botany at the Jardin du Roi. After having
dissipated a part of his fortune, he retired to Puiseaux, where he
established a distillery, the products of which he came regularly once a
year to dispose of.

There was an originality in everything that he did. His custom was to
sleep during the day, and to rise in the evening; he worked all night,
"because," as he himself said, "he was not then disturbed by anybody." His
wife, when she arose in the morning, used to find everything perfectly
arranged.

To Diderot, who visited him at Puiseaux, he put some very singular
questions as to the transparency of glass, and as to colors, and other
facts and conditions which could be recognized only through sight. He
asked if naturalists were the only persons who saw with the microscope,
and if astronomers were the only persons who saw with the telescope; if
the machine that magnified objects was greater than that which diminished
them; if that which brought them near were shorter than that which removed
them to a distance. He believed that astronomers had eyes of different
conformation from those of other men, and that a man could not devote
himself to the study of a particular science without having eyes specially
adapted for that purpose.

"The eye," said he, "is an organ upon which the air ought to produce the
same effect as my cane does upon my hand." He possessed the memory of
sounds to a surprising degree, and recognized by the voice those whom he
had only heard speak once.

He could tell if he was in a thoroughfare or in a _cul-de-sac_, in a large
or in a small place. He estimated the proximity of fire by the degree of
heat; the comparative fulness of vessels by the sound of the liquor in
falling; and the neighborhood of bodies by the action of the air on his
face. He employed characters