many
discoveries, which probably no one man, especially in such
circumstances, has ever made, it must be on an hypothesis not very
untenable, that some parts of physical science had already attained a
height which mere books do not record." "Unpublished MSS. by Leonardo
contain discoveries and anticipations of discoveries," says Mr. Hallam,
"within the compass of a few pages, so as to strike us with something
like the awe of preternatural knowledge."

[11] The plate is now to be seen at the Museum of Patents at South
Kensington. In the account which has been published of the above
discovery it is stated that "an old man of ninety (recently dead or
still alive) recollected, or recollects, that Watt and others used to
take portraits of people in a dark (?) room; and there is a letter
extant of Sir William Beechey, begging the Lunar Society to desist from
these experiments, as, were the process to succeed, it would ruin
portrait-painting."

[12] "16th Oct. 1787. In the evening to M. Lomond, a very ingenious
and inventive mechanic, who has made an improvement of the jenny for
spinning cotton. Common machines are said to make too hard a thread
for certain fabrics, but this forms it loose and spongy. In
electricity he has made a remarkable discovery: you write two or three
words on a paper; he takes it with him into a room, and turns a machine
inclosed in a cylindrical case, at the top of which is an electrometer,
a small fine pith ball; a wire connects with a similar cylinder and
electrometer in a distant apartment; and his wife, by remarking the
corresponding motions of the ball, writes down the words they indicate;
from which it appears that he has formed an alphabet of motions. As
the length of the wire makes no difference in the effect, a
correspondence might be carried on at any distance: within and without
a besieged town, for instance; or for a purpose much more worthy, and a
thousand times more harmless, between two lovers prohibited or
prevented from any better connexion. Whatever the use may be, the
invention is beautiful."--Arthur Young's Travels in France in 1787-8-9.
London, 1792, 4to. ed. p. 65.

[13] Mechanic's Magazine, 4th Feb. 1859.

[14] A writer in the Monde says:--"The invention of postage-stamps is
far from being so modern as is generally supposed. A postal regulation
in France of the year 1653, which has recently come to light, gives
notice of the creation of pre-paid tickets to be used f