The Baltimore County union. [volume] (Towsontown, Md.) 1865-1909, 1886-08-21
Correspondence Baltimore County Union.
SCIENTIFIC MISCELLANY.
nrrrrrsrD Color.


The ouantity of coloring matter which must be
mixed with a perfectly white powder-such as
carbonate of magnesia-before the human eye can
detect it has lately been the subject of some inter-
estine experiments, from which it appears that
red and yellow are most easily detected, sixteen
and seventeen parts respectively being sufficient
to perceptibly tinge 1OO,OOO,OOO parts Of white.
VALUABLE PLANTS.
In a recent geological paper, Prof. j. Starkie
Gardner sketched the value and Importance of the
grasses at the present day, remarking that they
occupy under cultivation one-third Of the entire
area of Europe, inclusive of lakes and mountains,
while, exclusive of malt and spirituous drinks
distilled from them, their products to the value OF
nearly one hundred millions sterling are imported
annually into England alone. There are over
5000 species fitted to occupy most diverse stations
and to overcome nearly every kind of vegetable
competition, with the result that about ninety
per cent. Of the plants growing in ordinary
meadow-land are grasses.
NATURAL TRAP.
A curious form of animal trap exists in the
Santa Paula valley, Ventura county, California,
where many unfortunate creatures are captured
by small streams of thick mineral oil which How
from the mountains during the summer down
ravines which are water-courses in the wet season.
Thus. it is stated on the authority of Prof. K. w.
Higard, gophers, moles, squirrels, rabbits, all
kinds of birds from the buzzard and hawk to the
canary, as we'll as all kinds of insects, may be
found just caught or completely submerged IN the
pitiless yiscid mass which rarely releases vic
tim once touched. The frequent occurrence of
bones of lambs and calves proves that even larger
animals are entrapped 1t is supposed that the
shining surface of the pitch gives the impression
that the streams are water.
WATER AS ANTI-FAT.
It has been matter of extensive belief IN France
that the drinking of water in considerable guam
titles has tendency to reduce obesity, by lncreas
ing the activity of oxidations in she system and
favoring the burning away Of accumulated fat
The error of this idea has just been shown by DR..
Deboye, who has proven that the quantity oil
water taken has no influence on nutrition or BODY
weight so long as the solid diet remains unchanged
SEED VITALITY.
The limit of life in the embryo of seeds has
long been a subject of experiment and discussion
In late lecture, Prof. Bentley, an English Dot.
anist stated that it is perfectly true that oats ana
other cereals have been raised from seed found
in a mummy's coffin, but that 1t appears 10 oe
equally certain that the grains were placed In TIE
ancient coffin by some means only very snort
time before the exhumation OF the BODY. MOI
many seeds will terminate under ordinary CIR
cumstauces after the third year, and very few IN
deed after the fourth. Peas and beans are very
tenacious of life. The lotus has been known 10
grow after hundred years, but there ls scarcely
another instance of such survival OF vitality.
HEAT OF THE GULF STREAM.
II is well understood that Great Britain and
other parts of Northern Europe owe much to the
warming influence of the Gulf Stream. The ex-
tent of the effect has been given in the calculations
of Dr. James Croll, who has found that the amount
of heat conveyed northward in the Atlantic by
this stream is equivalent to 10000 0O,-
600, 900 foot mounds of energy per day, which Is
equal to all the heat received by l,56O,935 square
miles at the equator, and more heat than IS con-
veyed by all the air currents. The heat OF the
Arctic seas and North Atlantic would be dimin-
ished that much by the stoppage or diversion OF
the great ocean river.
MISCELLANEOUS.
In Germany there are now eight schools OF
forestry, where training of FIVE years is neces-
sary for students seeking government positions.
France supports single school at Nancy.
From a comparison of the number of eminent
men of certain rank in each million individuals
of several races, Mr. Joseph Jacobs estimates
that the average Jew has four per cent. more
ability than the average Englishman, and two
per cent. more than the average Scotchman.
In new and elaborate work the bronze age
in Scandinavia, DR.. Oscar Montelius gives the
probable duration of the period as from 1,45O B..
c. to 400 or $50 B. c., when iron came into use In
northern Europe.
Astronomical photography continues to meet
with great favor in France. Since the successful
trials of the special photographing telescope at
the Paris Observatory, French astronomers have
decided to build three other instruments of the
kind, one for the Algiers Observatory, and two for
destinations not yet fixed.
During recent years great loss to farmers Of
Norway has resulted from disease affecting the
roots of barley. This proves to be due to mi
croscopic round worm, Tylenchts hordei, which
also attacks the roots of the bird-grass of Nor
wegian and Scotch coasts. remedy has still to
be sought.
In Sweden wood-oil is now made on an extern
sive scale from stumps roots and the refuse of
timber cuttings. In special lamps it gives very
satisfactory light, and is the cheapest of all ilum
mating oils.
An examination of 10000 prescriptions by
English physicians has shown the drugs most
used to be chloroform, bromide of potassium, sal
volatile, glycerne, syrup of orange peel, wine OF
ipecacuanha, sulphate of quinine, bicarbonate of
soda, carbonate of ammonia and bcarbonate Of
potash.