The Barre daily times. (Barre, Vt.) 1897-1959, 1914-09-12
DANGER OF ICE INFECTION.
Three Ways in Which Impure Is Rid
of Bacteria

The modern practice of using ice food
and drinks is so universal in this country
that it is important to determine to
what degree ice may be relied on as
not carrying infection. When in the
70s and SOS of the last century it was
shown that pathogenie bacteria might
survive freezing, ice fell under suspicion
as a possible medium for the transmits
sion of disease; yet few epidemics have
been ascribed to it, and the evidence
concerning these has been regarded as
inconclusive. H. S. Cumming in re
cent article in the United States public
health reports makes study from the
point of view of the source OF ice, the
physical and biologic changes accompany
ing or consequent OH its formation, and
the methods employed in its collection
or manufacture and handling.
Ice il either natural or artificial Tn
til recently, in order to secure clean,
Transparent artificial ice, it was nec-
essarv to distill the water used, thus de-
stroving all disease germs present.
With the newer methods employed, fill
dLsOH is 1tlu W Dt ShitiiitbN'
remarks that the fact, well known to
chemists. that during crystalization
nearly all extraueous substances are eX-
PEELED from the crystal, was overlooked
nv sanitarans until recently. As Whip
rio eays, "qualitatively the early BAG
teriologists were right; quantatlvely
they were wrong" In the formation of
natural ice. most OF the impurities are
expelled into the waters OF the pond or
stream; and the same result is attained
BY the newer methods of artificial lee
making. BY the "can" method, cans
of water are immersed in the freezing
mixture As the freezing proceeds, the
impurities are forced toward the center
In one of the newer methods, large cans
are used. and the cakes of ice are cut
into smaller ones, eliminating the dirty
core. By another new ''can" method, the
impurities are expelled into about six
inches of water kept liquid by agitation.
In the plate" method, the water is con-
tanned in large tanks, on one side Of
which are pipes containing the freeing
mixture. The water freezes next the
pipes in plates about ii inches thick,
and the impurities are expelled into the.
water beyond.
Some natural ice is undoubtedly de-
rived from polluted rivers or ponds.
Three great factors tend to purity ice
from polluted waters; The first, rs just
mentioned is crystallization. The see
ond is comparatively fact that freez-
ing destroys large percentage OF bac-
terra The third and most important is
time. Tile longer the time intervening
between the infection of water and its
use las water or as icel the sllghter
the chance of the survival of the germs.
On this score, natural ice, which is col
lected and stored for several months be-
fore shipment. has the advantage over
artificial ice, which is usually marketed
soon after it is made. Owing to these
three factors-crystalliz tempera
ture. time--clear, clean ice is OF itself
as free from danger as could be wished.
Artificial ice made from pure water IN
clean, sanitary factories may be regarded
as safe; so also may natural ice cut
from reasonably pure deep ponds or
lakes and stored under sanitary cond' 4
tons. Artificial ice made from polluted
water in dirty, insanitary factories IS
unsafe; natural ice cut from shallow
polluted ponds or from grossly polluted
rivers is also unsafe. Any dirty-appear
ing, cloudy ice snsy be infected as well
as polluted; no such ice should be used
in contact with food or drinks. Ice
which is otherwise safe may become IN
fected by improper handling-hy being
dragged across dirty streets or side
walks or distributed by unclean hands.
This is the great source of danger. Sum-
ming up the situation, the Journal of
the American Medical Association says
that we may practically eliminate dan
ger by avoiding the handling of ice with
dirty hands. by washing the ice with
pure water, and by using only clear ice