The citizen. (Frederick City, Md.) 1895-1923, 1897-05-28
written for the Citizen.)

written for the Citizen.)
asThe size of the drop, so much used
in measuring powerful drugs, can be
made to vary in a most alarming aud
little appreciated degree. Dr. George
f. Payne meations an instance in
which physician obtained 40 drops to
fluid dram from a one-ounce glass
stoppered bottle, and on dropping the
substance-dilute hydrocyanic acid-a
most deadly plisou-back again from
narrow-lipped graduate the number
was 100 The anticipated number was
go. In experiments with fluid dram
of water, Is drops Were had from the
bottom of teu-Ouuce evaporating
DISH "a from thick, square-ended
twopint funnel, choIied with stop
per for dropping; 30 from glass stop
per inches in diameter; As from
tw0-ounce Tipped graduate; 81 from a
two-ounce cOrk-choked funnel with
slanting end; 50 from 3l7-ineh guild
ing rod taking supply from one-gram
graduate; 100 from fve-ounce Tipped
beaker 100 from a five.ounce Tipped
beaker with 3l6-iHch guiding ROD; 100
from l-24-inch guiding rod point
from two-Ounce dropping funnel; and
800 from a 1-40-nch guiding rod point
from a twO-Ouuce dropping funnel
BY the methods usually employed, the
drops varied from 80 to l20 to the fluid
dram.
The location of the sta ions for the
proposed earthquake survey of the
world is now an important problem.
The use OF existing astronomical OBJ
servatories has advantages, but Prof
u. GrablOvitz points out that most of
active volcanoes
three circles and suggests that the
earthquake stations should be estab-
lished near the six points of intersec-
ton of these circles aud at twelve
other points symmetrcally placed on
the circle.
Acute rheumatism is regarded by Dr.
Jaccound as of bacterial origin aud he
looks upon the case of child born
with rheumatism while its mother
was suffering from a severe attack as
evidence OF the infectious character of
ar the disease.
Afnd FL
On. The Whatever new sources of rubber |
ring nay be discovered, according to Mr. |
John h. Jackson of the Kew Museum,
IL IS pretty certain that the plants |
Welding the elastic juices must belong I
p ono of tho -, - natural orders of |
Euphorbaceae, Uricaceae or ApOuy- !,
naceae. Hevea brasiiensis, the source
of Para rubber, is the best known of
the rubber producers, and is tree
growiI : TO height of go feet in the
forests of tropical America, especially
along the Amazon. This aud Central
American rubber tree (Manihot Gla-
ziovii) both Of the same order, have
been very successfully introduced In
other countries, especially India and
West Africa "A species of the Urtic-
acceae (Castilloa elastica) furnishes
the Guatemala, Mexico and West In
dies rubbers another species (Ficus
elastca) the Assam rubber, and third |
species lFicus Vogellil) poor Lagos |
49, rubber. What is known African |
rubber is furnished bY several shrubby |
climbing species Landolpha owarien- !
sis, l., florida and l.. KIrkii) Of the |
Apocynaceae. The new source of La
gOs rubber which nas suddenly devel- |
oped one of the most important indus |!
tries of Africa, is the Kicksa afrlcana, |
which is of the same order, but
is u tree 80 or go feet high with a trunk |
II or IA inches in diameter. 1t is one
of the most beautiful trees of the forest |
with yield in good season of 10 to
10 pounds of excellent rubber per tree. |
In January, 1895, the trade in the rub
her began with q, l3l pounds of ex-
ports, but at the close OF December the
total had grown to 5,069, 504 pounds for
the year. Several other eastern species
of this order yield small quantities of
rubber. The efforts of Kew authorities
to extend the growth of rubber plants
in all favorable climates have been so
successful that, with the additions to
be expected from new sources, Mr..
Jackson believes the supply may be
kept up even to the demand so rapidly
increasing through the growth of cleo
trical, rubber-tyre aud other industries.
N
The curious discovery has been made
kxo
polished plates of aluminium adhere as
s If soldered after being pressed closely
together for eight hours at a tempera-
ture of $500 G. 1929 F. Platinum and
other metals behave similarly. To sue
cessfully show the phenomenon, the
cause of which does not seem to be
clearly understood, the plates must be
perfectly cleaned, and contact must be
complete at all points.
Plants, like animals, have kind of
fever after being wounded. In obser-
vations made some time ago, Mr. ID.
NJ Richards proved that respiration is
increased in the injured plants, aud
he now finds that there is also an III
crease of heat The disturbance Of both
respiration and temperature runs def
Unite cour,e, attaining q maximum
some tweDty-four hours after injury.
The increase of heat il, of course less
perceptible in the plants, but compared
with the ordinary temperature of
plants in relation to the surrounding
medium, the rise after injury is as
great as in animals, if not greater. The
maximum in all plants seemed to be
two or three times the ordinary excess
above the surrounding air.
A comparison of various pavements
has been made at Wolverhampton
England, 10y local engineer. The
materials being laid ON Portland &C.
ment concrete 6 inches thick he finds