The citizen. (Frederick City, Md.) 1895-1923, 1896-07-03
written for the CITIzEN.l

the heat generated by the internal frlc-
ton of the heaps from the rolling OF
the vessel This has led him to pat
ent a method of ventilation having
the three-fold object of drying the coal,
removing the evolved gases, and pre-
venting the mass from moving about.
His plan is to perforate the floor of the
hold and to set up pair OF perforated
walls down the centre, thus forming
an air space in the form of an inverted
T, which is connected with double
ventilating coWI on deck. In addi-
ton to the partition walls, number of
movable perforated pipes are to run
from the central shaft transversely
through the coal at different heights.
The experiments of Mr.. T. e. Por-
ter, of Eton College, that Rontgen rays
are of a. least two different kinds. To
the kind he designates X, flesh is fairly
transparent, bone opaque; but to the
rays he calls X1, flesh seems nearly or
quite as opaque as bone. The former
rays are those ordinarily produced in
the cold. But if the tube be heated,
these rays gradually disappear and the
X2 rays take their place, until the
bones of the hands are no longer VlSl-
BILE in the horoscope, although the
screen is still brightly illuminated and
the shadows distinct. Beyond GER
tain temperature the emission OF any
rays capable of exciting tiuorescence or
Photographic action seems to fall off
rapidly.
The two occiptaf lobes of monkey
were removed by M. Alexander n.
Vitzou on February 10, 1898. AS usual
in such case, the animal totally lost
its sight. In the fourth month after,
the monkey began 10 show evidence
of perceiving objects, at the end flour
teen months it could readily avoid OBJ
jects, and on April "a, 1895, NJ. Wit
ION was astonished to find the place
originally occupied by the two lobes.
had been filled with brain substance.
Since last January an interesting ex-
pertinent with sewerage has been in
progress in Exeter, England. A meth
cd devised by Mr.. F. j. Cummin, the
city surveyor, is used, and is known as
the "Septic Tank System" 1t deals
with ABOUT $500 gallons per day as
now tried, which would represent the
sewage OF from 800 to 400 people. The
tank is "a feet long by 8 feet inches
wide, and about feet deep, and is
arched over and covered with earth.
It's capacity is about 5000 gallons.
During its passage through this tank,
occupying about twenty hours, the sew
age is cut off from light and air, but
no chemicals or other ingredients are
added to it. The inlet and outlet are so
arranged that the upper portion of the
contents is undisturbed. A sewage
scum forms on top, eventually reach
ing inches in thickness, and by this.
all soluble solids are thrown into solu-
ton bv meteorological action, the out
flow from the tank being com paratively
clear and odorless, and considered fit
for discharge into tidal water, or for
filtration, or for utilization on land.
AS the result of competition opened
in 1894, the city of Paris received 148
schemes for purifying river water for
drinking. Most of these were wild or
amateurish, but 20 were retained for
further consideration, of these being
based on the action Of heat, II on me-
chanical treatment or filtration, 6 on
chemical treatment, and providing
for mixed treatment. Experiments by
a commission have shown that the
methods depending on heat are too
costly, the mechanical systems require
frequent cleaning, and the chemical
methods are Impracticable. On the
whole, mixed treatment, the addI-
ton of chemicals being followed by
filtration, has been recommended. Such
a process gave nearly 1000 gallons per
day from IL square feet of sand filter,
the organic matter being reduced 80
per cent. and the bacteria 99.77 per
cent, but the working was not always
regular.
The percentage of red and green col
Or-blindness among Chinaman has
been found to be about 8. or not very
different from that among Europeans.
Fully half of those tested by DIR. Fielde,
of Swallow, however, mixed up blue
and green, causing him to believe that
many Chinese are quite blind to the
violet colors.
The proposal has been made to the
British archaeological Union that the
birds be classified in a hand book divid-
ed according to the six great geograph-
ical parts of the world. Each division
would form volume containing 1000
species.
The cracking of rubber goods is ex-
planned by Mr.. Frank W. Birchall, a
recent writer, as an effect of the oxida-
ton of the caoutchin, the essential oil
of caoutchonc INFLAMMATION does not
lessen the affinity of this substance
for oxygen. The compounds used tend
to fill the pores of the rubber and thus
somewhat reduce the opportunity for
oxidation, but the metallic oxides and
other substances introduced in vulcan
ization aud dyeing-including sulphu-
ric acid from anthony sulphide-are
often injurious, and boiling in caustic
soda to remove the ''bloonl" left on
goods by an excess of sulphur may
cause injury. A comparison of anal
Uses of the damaged rubber with those
of the sound shows a very large in
crease in the percentage of oxygen and
some loss of carbon and sulphur. The
hope is expressed that rubber may be
produced synthetically ere long, thus
removing our dependence on the pres
ent precariOus source of supply.
curioIls case of ssmimicrvu has been