The citizen. (Frederick City, Md.) 1895-1923, 1895-12-13
(Wriltenfor the CITIZEN

important department of knowledge,
and governments and municipalities
are establishing laboratories and insti-
tuting researches on large scale that
must prove OF great benefit to man
kind. Bacteria are not only disease
producers, but they manufacture
host of products that are beneficial
and essential to life. If we could
s. parate the industrial germs from
the disease producers aud domes-
ticate the former while we we drive
the latter out of existence, life would
be more worth the living. This is grad
ually beings attempted. Bacteriologi-
cal analysis of water is showing us how
to keep such germs as those of
typhoid fever out of our cities; study
of milk is making it possible to reduce
tuberculosis, which is thought To he
largely spread 10y milk and butter
from con sumptive cows; some veteri-
narians claiming that 30 per cent.
of all cattle are affected. Meat is less
dangerous because cooking de-
stroys the bacteria, but European
cities have guarded themselves even
against diseased meat by a system of
Inspection. The yeasts plants now re-
lated To bacteria, are found to be quite
numerous, and are now regularly pro-
duced III culture free from bacteria.
This has revolutionlzed German brew
ing and other industries. Almost any
desired bouquet is given to wine 10y the
proper germs and cheese is similarly
favored. Bread from the pure yeasts
is sweeter and more digestlble. In the
s'l, the s0-called nitrogen-forming bac-
terla are more necessary To the growth
of food plants than anything else, and
Instead OF using tons of fertilizers, the
future agriculturalist will cover his
fields with cultures of the nitrogen
germs and get better results. We will
even have special grounds for special
plants. Considered thus only as relat-
ed To food, haclerology has made great
advances, but tuese are nothing COM
pared with what is yet to come.
The research laboratory just opened
| III Paris seems to mark "a new stage ia
scientific progress. For nominal
! monthly sum paid to the Municipal
Council, any person may Use The lanu-
ratorS and will b. provided with ma
terials for the experiments.
X
A minute trace of foreign substance
often strikingly affects the woi king
properties of "a metal. few impurities
actually improving the pure material,
while most of them impair it, An at
tempt, according to ii Mason Co leye
lecture 10y Mr.. Mem llan, has been
made to connect these effects with the
relative volumes of the atoms of the FL
ements taking part, those impurities
having larger atoms than the orIyluul
metal often causing deterioration and
those with smaller atoms giving no ei-
feet or else Il good one. In allows. the
results OF adding increasing quantities
OF one metal to another are vsry varia-
lie. IhuS, IN braSS, the addition of
zinc to copper first causes Il somewhat
irregular rise III the strength Of the
copper until ~ per cent. of zine has
been introduced; next Il slight falling
o1f nnul the proportion of 30 Zinc and
40 copper Is reached; then rapid in
crease I" the maximum strength with
the mixture of ~ Zlnc and 50 copper:
and t1ually decrease to the minimum
of strength with the alloys containing
90 to 40 per cent. of zinc, which are in
tensely hard and brittle. Bronze gives
a somewhat similar curve, as do also
gold with aluminium, nickel and iron.
ana other alloys. 1t appears that a few
alloys are undoubted chemical com
| pounds, about Il few others there must
sIill tie uncertainty, while in the major
! lty OF cases only mechanical mixtures
are formed. Where true chemical
compounds exist the alloy usually has
undesirable mechanical properties, aud
| reasoning from the fact that most
chemical compounds have properties
widely different from their compliments.
It seems useless to seek compounds
from mixtures in atomic proportions.
The prospect that actelyne will soon
come into extensive Use for lighting
has led DIR. w. III. Birchmore to inves-
tlgate its possible dangers. He finds
that one part III 10000 may become
dlffused in the al: of room without
detection by smell, and that this
amount can produce dangerous effects.
and even result fatally if breathed for
number of hours.
The land crab has been put to work
III the cause of science by Mr.. James
Sterling, assistant Geological Surveyor
III Victoria. Noticing that this exca-
waiting crustacean brought up pieces of
rock from the subsoil, he caused bur-
rows of the crabs to be carefully watch
ed, when "a miner detected small pieces
| of coal around one. A shaft was sunk.
resulting in the discovery of a coal
seam. Crabs are now regularly en-
ployed by the Geological Survey where
alluylum covers the rock.
| \ \
The great progress made in the
Swiss national industries during the
last htteen years is pointed out as a
remarkable example of the Influence
OF State and Municipal establishments
for technical education. The skill and
artistic knowledge impaired supply,
especially, what is most required in
the production of the finer grades of
goods. In the cantOns of Geneva and
NSHehtal, with a population scarcely
e&eeedinglz2 900, there are five schools
lot watclinakers, aud these cantons
and Chaux de Ponds have schools for
instruction in tue fine arts and in ar
tisllc handicraps. There are also com
mercial schools and the professional
schools in which various Industries are
taught to both sexes. In the Geneva
matchmaking school girls are instruct