The citizen. (Frederick City, Md.) 1895-1923, 1895-04-05
prepared Weekly, Tor the, Citizen,

uted in zones whose limits follow lines
of equal temperature, but just when
the temperature eXers its restraining
influence has been matter of uncer-
tainty. In his recent study of the
problem for the United States, DIR. G.
Hart Merriman has considered that
not only the mean temperature but
also the total quantity of heat in par
ticular zones must have an influence.
He measures the total quantity of heat
by the excuses over ~ degrees, the
temperature at which physiological ac-
tivlty in plants aud reproductive activ-
ity in animals are assumed to COM
mence, and arbitrarily takes the six hot
test consecutive weeks of summer as
the hot season of the year. Charts con-
structed according to these eonsidera-
tions, aud compared with chart of
life zones AS mapped out two years
ago, show surprising condolences,
leading DR.. Merriman to conclude that
the various zones of the different
species are limited uorthward by the
total quantity of heat during the sea-
son of growth and reproduction, and
southwark 10y the mean temperature
OF the hottest part of the year. The
overlapping of northern and southern
types on the Pacific Coast is explained
by this theory, as here only is high
total of heat combined with very
mild summer.
An incubator for Matching hens
eggs under reduced atmospheric pre-
sure has been devised by Prof. G.. Gia-
comlnI, an Italian embryologist, who
expects the apparatus to prove "A valua-
Die aid in the study of teratology.
Reduced pressure In the early days If
development incites various mOnstrus-
tiles, besides retardlng growth, but in
later st ,geS embryos are killed unless
"Nysvn Is added to cuuuteract the eff
fects of the raretied air.
In a comparison of several thou.
sand cases, DR.. korosi, of Buda Pesth,
finds the proportion of deaths from
weakly constitutions, or maladles
traceable to the mother, to be twice as
great among children of mothers under
20 AS among those of mothers over 80.
A case of double brain action of
much apparent significance has been
recorded 10y DR.. l.. &. Bruce, in Brain.
In one condition the patient spoke In
English, in the other his language
was Welsh. In his English period he
was the subject of chronic mania
He was right-handed, showed fair in-
telligence, aud remembered clearly the
events of the previous English periods,
but had no recollection of the Welsh
portion OF his existence. He wrote by
preference with his right hand in the
usual way; but on request would write
with his left hand, in that case pro-
ducing mirror writing-that is travers-
ing the paper from right to left.
When in his Welsh period, however
he was left-handed and the subject
of dementia His speech was almost
unintelligible, but was in Welsh so far
as could be understood, and he had no
idea of English. His mental aud
physical conditions altogether were
the reverse of what they were in the
English stage. These observations
convince Mr.. Bruce that the right and
left hemispheres 3f the cerebrum are
capable of independent action, each
controlling the PERSONS thought and
existence during its active period, aud
alone receiving the mental impressions
of that period.
Since last August gas engines have
been used at CreSden t. drive street
cars on a line about three miles long.
The engine, which is placed under
one OF the seats, is of 9-horse power,
and has two cylinders, the ignition be-
ing effected by electricity. The gas is
stored under pressure of l20 pounds
per square inch in three cylinders,
each having capacity of 331 cubic
feet The engine is not stopped while
the car is in service, connection to the
wheels being made through movable
clutches, which can be manipulated to
stop or reverse the ear. A speed of 8
miles an hour can be attained with a
car carrying SO passengers, the cost per
car mile being about 10 cents, with gas
at Sl.O0 per 1000 cupic feet.
1t is now well recognized fact.
states medical journal, that the struc-
lures of the eye, especially the cornea
and c0njunctiva, are subject to mala-
rial affections, periodical in character,
differing from the usual affections of
these parts, but involving actual tissue
change, and amenable to quiniue or
other anti-malarial treatment. Some
liberation or abrasion of the corneal
epithelum may occur, or intra-ocular
hemorrhage during the cold stage of a
paroXsm.
Electricity steadily brings the mil
lenium nearer, the thawing of frozen
water-pipes being among the latest of
domestic applications. The originator
OF the idea Uses a special wire, in
which the current is conducted through
hlghly-resisiant metal, insulated
with fire-proof and non-conductlng
medium, the whole enclosed in IA metal
tube, which is drawn down to make
compact wire or tube that is exter-
nally conductor of heat but not Of
electricity. The internal resisting metal
becomes strongly hdated, while the |
insulation prevents loss of current and |
electrolysis. The prepared wire was
placed In waste pipe in which mass
of ice II inches long and u inches |
thick had formed, and with current !
OF 4 amperes at a pressure of 80 volts, |
complete thawing was effected in |
minutes.