The citizen., 1899-04-21
I LMrItten for the Citizen. }

iHII'NSlbi', WIN i"l' 'NN' ~ i'ii's
is stated by Mr.. Il. De c. Ward,
of Harvard University, to he a
matter on which authorities are
agreed. The chief factors of dan
ger are the combination of heat
with humidity and the prevalent
diseases Much may be done to
mitigate these evils by hygienic
measures, care in drink, the use
of cereals instead of meats and
well regulated exercise. The
healthy districts are high and
dry. The three diseases especial
ly prevalent are Sunstroke, NAL
aria and yellow fever--the first
chiefly Influenced by the rains,
the second related also to soil
aud the last finding its check in
elevation. The upper limit of
yellow fever is about 500 feet in
the United States, 1900 feet in
Mexico and 1000 feet in jamaica.
Mod ru methods of obtaining
gold from low grade ores make
available supply of the metal
almost beyond conception. An
old lake bed of Utah is a mass of
limestone eight miles 10y ten, and
twenty to forty feet thick, and
this. accordiugto Mr.. \. +. Outer,
bridge. ,Jr.. has been estimated to
contain $4,000. .000. coo of gold
The clay under Philadelphia was
forty years ago calculated to
hold more gold than had been OBJ
tanned from California and Aus
tralia, clay hardly richer being
now proftably worked in Calitor-
MIA.
In the little furnace by which
GoldSchmidt obtains a tempera
ture of over 2.O00o c.. the fuel is
aluminium mixed with iron rust.
and this is ignited by a Shellack-
ed bead of the aluminium (Which
is pulveriZed, Of courSe) and per
oxide of harium, into which a
piece of magnesium wire is insert
ed. There is scarcely a metal
known that cannot be reduced in
this furnace. The containing
vessel may he Of wood lined with
sand and the heat can he regulat,
ed by varying the quantity of
the mixture.
A German method Of restoring
the luminosity of WelShbach gas
mantleS, which becomes reduced
after Il time. consists in blowing a
current of air through the mantle
from the inside while the lamp is
burning.
Instances Of sudden and fatal
changes in the condition of sick
| persons during a storm must have
been noticed by many. The sig
( niicance of this is pointed out 10y
Dir. I. w. Burwood, who, on the
unexpected death Of an aged
! patient after only few hours of
unfayorable symptoms, had his
attention called to the fact that
a strong gale had been raging
during the night, with a fall OF
barometric pressure of nearly tive
inches. DR.. Burwood reflects
that the harometerS extreme
range of fully two inches must
mark a change of about lac
] pounds per square foot in the
weight of air resting on the
earth'S surface. In the case o
his patient. the heart had beaten
StrenuouSly for some weeks
against the high pressure and the
J sudden removal Of pressure haC
y. caused the action of the heart tc
be greatly increased, with tn,
result that a eliot in its cavitie,
was gradually formed. He ha,
known many similar cases. II,
therefore asserts that a large par
of the sudden deaths reported il
the morning papers will be found
To have followed a rapid fall q
barOmetric pressure and that thi,
will explain many unlocked foI
fatalities that have puzzled even
/ medical men.
Electro chemistry, now in it
infancy. offers possibilities for til,
future that are quite bewilderiug
y late suggestion by Mr.. Thoma
Swan is that by compresSing sui
phur dioXide and air into separat,
carbon tubes. dipping in sulphur
acid the two gaSeS-the forme
the familiar gas of burning sui
nbur NOV Ian u,oJa q, ,,,,;tn