The Saint Paul globe. (St. Paul, Minn.) 1896-1905, 1903-04-05

mostly an achievement of the TWEEN
tfeth century. The great map of the
United States, begun twenty years
ago, will require about 100 years for
its completion, and the chief of the.
photographic Office reports that the
1880 chart plates In his possession rep
resent only about one third of what
are necessary before the seas of the
world will be sufficiently charted for
safe navigation.a II
The phenomena of electric dis
charges in vacuum tubes give US the
nearest approagh to seeing electricity
that we are likAly#fo make, states Sir
Oliver Lodge. The streams of cor
puscles propeller along the tubes sug-
gested to Crookes i 1870 the idea of
a fourth states3ofs matter, and these
corpuscles- smaller than atoms and the
same in all kinds Of gases-were NAM
ed electrons bygStoney, and have come
to be regarded as the electric parts of
all atoms or even as making up mat
ter itself. When torn from it's groups
or from matter the electrOn travels
with a speed comparable to that of
light. A body charged with electricity,
|. if at rest, presents the phenomena of.
electrostatics: If in motion, those of
|, electricity and magnetism; if in aceel-
aration or change of motion, those Of
/ light and radiation generally.Some SUBJ
StanceS-Such as uranium, poloniun,
and radium-throw off electrons with
out stimulus, giving very intense and
penetrating rays, with a kind Of cleo
trical evaporation. This property of
radio activity is found in many bodies,
even in leaves and newly fallen rain
drops, and it will soon be difficult to
find any substance without it in some
degree. On the hypothesis that matter
is composed of electrons, their size is
known to be about the hundred-thou-s
sandth part of the diameter of the
atom. In an atom of hydrogen there
of mercury there are 100000; but even
in the latter they are shown by
calculation to be about as far apart
in proportion to their size as the
planets in the solar system. By their
force the atoms come to be impenetra-
bic. OF the fundamental properties of
matter inertia is quite certainly known
to be electrical, cohesion is being
shown to be sosTbut gravitation is still
| mystery.
In the electrical ore detector of Leo
Daft and Alfred Wllliams, the second
airy current of an induction coil is
taken to two from rods. which are
stuck into the ground to a depth of an
| inch or two at al distance apart of
some hundreds of yards. The presence
of a mineral vein Of higher conduc-
ttvity than the average ground changes
the electric waves radiated from the
rods. When two other rods connected
by telephone care moved about any
change is made audible. and in this
way lead and zinc ores have been To-
Gated in Wales ana hematite in Eng
land.
The curious phenomena of sym
| philism'' are being investigated by E.
Wasmann. a German zoologist. This is
/ the harboring of foreign species of in
sects, etc, in the nests of ants and
| termites, and it is found that more
than 100 species of arthropods, Or
creatures with jointed legs, are thus
associated with the ants, at least S5
| or 80 species being beetles. All arr
ties. Most notable among the charac-
teristics of these beetles are their oily,
/ reddish yellow or reddish-brown col
or, and special exudation organs, or
! pores. with brownish hairs. but there