Amador ledger., 1907-01-04

tant matter in such operations as eX
ploding torpedoes-M. Branly has
projected an ingenious though COM
plIcated apparatus. wheel has a
non-conducting rim with five con-
Quoting pins at equal distances, and
cam is placed so as to move lever
and start the action. of the mechanism
when the wheel makes a complete
turn. Two flexible brushes make
contact with each other through the
pins. Tho receipt of an electric i'm
rate to the first pin, another wave
sends it to the second. and so on,
but if no wave is received as pin is
reached, the wheel drops back to
starting point. A contact with each
pin last only one-twentieth of a
second, there is little proba ability
that the precise moment would be hit
five times in succession by any ran
dom shower Of sparks from an enemy.
Radiations from ordinary substances
have been studied in Germany by F.
Streintz. In gas containing oxygen,
such metals as magnesium, alumni
um, zinc and cadmium give off in
visible rays-pIesumably like ultra
violet light-that ionize the surroun-
ding gas and act as Photographic
plates. OF practical interest is the OBJ
servation that metals may be protect
ed from rust by electricity.
The Importance of gas as source
of energy is shown by the fact that
Germany's iron and coal industry
alone uses about 400 large gas engines
with a combined capacity Of 42O, 600
horse power.
The primitive life of the earth com
prises a multitude of microscopic
forms, each of a single cell or group
of simple cells, and some not dis
tinctly plants or animals The
bacteria have been assigned to the
special science of bacteriology, forms
having vegetable mode of life are
claimed by the botanists, aud the
protoZoa are ranked as animals. The
bacteria were formerly looked upon
as the sole agents of disease, but re-
cent researches prove that perhaps
fourth of the protozoa exist as para
sites, and play a part in the disorders
of man and other creatures. The
malaria parasites became known in
1880, those of the Texas fever of cattle
in 1893, and those of tsetse.t fly disease
in 1898. These sensational discoveries
have opened a wonderful new field
for investigation, and have trans
fol med all plans for making habItable
certain disease infested regions. Nal
aria, for instance. is now known to
be due to parasites spread by mosqui
toes, instead of being attributed to
bad air from marshes. The malaria
parasite is digested in all stages in
the stomach of mosquitoes of the
genus CuIex, but in the AnopheIess
mosquitoes certain stages resist diges
ton, the parasites multiply, penetrate
the stomach walls, and produce an
immense number of germs which
eventually reach the salivary glands,
when the mosquito becomes infect
lous. Similar organisms, with differ
ent methods of distribution, seem to
prey on many animals. Our know
ledge is just beginning, but has al
ready developed a new science of
protozoology, of which special chair
has been established at the Uni7er-
sity of London.
Breathing through a wet handker-
chief at night has given relief to hay =
fever patients. This has suggested to
DR.. A. q. Heath, novel filter, which
consists of two rings connected by a
bridge, each ring having stretched
over 1t a fine netting of silk gauze.
The rings are to be worn in the nose,
half an inch from the openings. This
device has been tried without dis
comfort in a number of severe cases
of hay fever, and the removal of
pollen or dust has invariably improv-
ed the breathing within fifteen
minutes to an hour.
Exposure to the sand blast for two
or three minutes cuts away road and
floor materials as much as months OF
ordinary wear, and it has been found
in Germany that this is the best
method of testing such materials. a
special apparatus has been made by
Alfred Gutmann, near Hamburg
Test cubes OF 2 As inches to side
are cut with a diamond saw or mold
ed, and one side of the cube is parti
ally covered, so that a circular area
2 % inches across is exposed to tht
sand thrown up by jet of steam
escaping from pressure of two
atmospheres. Natural quartz sand l!
used, with rounded grains passing
through a sieve of ia meshes PEI
square inch. The abrasion shows thu
quality and the characteristic pro
perties of the material, the homo
geneity of the different parts, tn,
coarseness of the grain or tht
peculiarities of structure, and th
uniformity or irregularity of wear
Granite, porphyry, blast furnace