The Baltimore County union. [volume] (Towsontown, Md.) 1865-1909, 1904-01-23
CorrsspOndencs Baltimore County Union.
SCIENTIFIC MIS- CELLANY.

Correspondence Baltimore County Union.
SCIENTIFIC MISCELLANY.
A Natural Drier- The Sleeping Sickness
Parasiee-Hair as the Chemist Sees Il
Action Of Magnets on Animals-Fer-
ro-Concrete Pipes--Dark- Ray Photo
graphs-The New Map-Making--Bot-
tied Refrigeration.
The best drying OIL, stated by the French con-
sui at Canton to enter into Chinese lacquer. Is
pressed from the fruit Of the oil-tree (Elaco-
cocoa vernieia, cordata or verucosa) which grows
IN China, Southern Japan and Cochin China
The fruit yields about 40 per cent. Of oil. This
has density Of 0.9iO is golden yellow in color,
rapidly hardens through absorbing oxygen, and
has some curious properties, such as that of
hardening when heated to 2OOOC. and of losing
this property when kept for time at 1902. The
oil serves in varnishes and for interpreting
fabrics. tbs gradually becoming better known,
but, although introduced into Europe about
forty years ago, its export to Germany, Ameri-
ca and England in 1897 had reached only 20 tons
out Of total production Of 1880 tons. It's
light color gives it an important advantage over
linseed oil.
The studies Of the mysterious sleeping sick
ness Of Africa are yielding interesting results.
In all stages parasite trypanosoma-is found
TO be present in the cerebro-spinal fluid but In
certain fever cases a similar parasite has been
discovered in the blood, though not in the
cerebro-spinal fluid. Sleeping sickness proves
to be confined to a belt Of country fifteen miles
wide on the northern shores of the Victoria Ny
anna. A tsetse fly is very abundant. and it is
suggested that this fly may convey infection,
just as one conveys the species Of trypanosoma
- ~ - 49, 1~k1.<
animals is due.
Human heads are characterized by potassic
hail, siIicic hair and sodic hair In the new clas
sifcation of N. j. Gaube, French chemist.
He finds blonde hair to contain much soda and
also much silica; red hair to be especially rich
in silica, and black hair to have a great deal of
potassium. but little soda and scarcely any
silica.
That living organisms are affected by a mag
netic field seems to have been proven at last by
Messrs. Cheneveau and Bohn, of Paris. Gull
lures Of various kinds of infusoria-
rous and herbivorous, fixed and swimming. ma
rine and sh-water-were divided into two
parts, and one portion was kept under ordinary
conditions while the other was treated in exactly
the same way except that it was placed in q
tube between the poles of powerful electro
magnet. A jacket of circulating water shielded
the tube from heating by the magnetizing cur
rent. The first effect was the lessening of the
cilIary movements of the swimming organisms,
but in the continuation of the experiment
which lasted from three to i've days-the growth
and multiplication of some specimens were ar
rested, and some varieties Of the infusoria were
totally destroyed. 1t remains to be shown
whether more complex animals may not be af-
fected by the powerful magnets now so COM
monty used.
Concrete strengthened with steel-or ferro-
concrete-is being used for water mains in Bel
ei,ana, For moderate pressures--that is. heads
below 60 feet-a skeleton Of steel bars of double
7 section is prepared, some of the bars running
lengthwise of the pipe, while these are wrapped
with spiral of similar bars spaced according
to the pressure to be borne. The skeleton, in
lengths of ten feet, is placed In vertical mold,
which is then filled with quick-setting cement.
For greater heads up to the maximum of 1888
feet the basis Of the pipe is steel tube LIS
inch thick, with steel skeleton both inside and
outside.
Some remarkable photographs of landscapes
have been exhibited to the Vienna Photographic
Society. These pictures were taken with the
new light filter of Herr Elder, and they show the
objects as illuminated by invisible ultraviolet
rays. The filter combines cobalt glass with nj
troso-dimethylanilin, yellow dye that absorbs
all visible rays but transmits the whole Of the
ultra-violent.
sss
The notion that q wet season in England is
followed by one in Australia has been disproven
BY Mr.. H. c. Russell.
-
A map in relief gives much more accurate
idea of the geography of a locality than the or
binary charts. The ordinary relief models are
expensive, but for several years Mr.. Patteson,
an English draughtsman, has been experiment.
ing in Belgium with relief maps, stamped by
hydraulic power in metal, that can be rapidly
reproduced in considerable numbers. The map
is first printed on the sheet Of metal. The
drawing requires special skill, as the different
geographical points are not In accurate position
at first, but are placed that all points will be
correct after the hydraulic impression. In an
example shown to the Royal Geographical Soci-
ETY. Of London, one of the most precipitous
parts of Belgium was represented in strictly ac-
curate relief The process required pressure
OF about so tons, and the best metal seemed to
be red copper, although aluminium could proba-
bly, be used. A scale as large as to 100000
must be adopted. as otherwise the relief would
not be evident without the disapproved plan Of
exaggeration.
Liquid air has gained Roadway slowly on ac-
count Of its utterly unfamiliar nature, but
when better understood its many possible appli-
cations may make it an every day necessity. It
is now supplied in Berlin at about % cents for
two quarts. This quantity Is held in glass re-
ceptacle, which has double walls with insulating
material between. the walls being silvered and
the whole enveloped in insulating material. In
this vessel the air retains its temperature and
liquid condition for fourteen days. few drops
freeze glass Of water when poured into it, and
refreshing drinks and air betterment in sick
rooms are among the uses suggested.
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European bad weather of the past summer has
been attributed by Prof. Benseler, of Coffin
gen, to the volcanic activity in Italy, Iceland
and elsewhere since the eruption at Martinique.
The heated air from the mountains has been
carried eastward by the prevalent winds, and
has caused the late continual rain and fogs of
the Continent.