Orange County observer. [volume] (Hillsborough, N.C.) 1880-1918, 1899-05-25

It is generally believed that
common house martin, which ie9
England when nesting time Il Oh
spends the winter in Africa. Butt
though millions Of the birds disspH
from Europe every autumn, the
biologist, DR.. Sharpe, knows OF
one single authentic Instance OF
capture of . martin in the African
tinent.
In a late volume DIR. A. Il. Flf
says that Though u own sun
passed the zenith of its career, 1T
in the remote future, brighten 7
rivalry ~ith Sirius itself, whichI
seventy-ive times hotter and brigH
than our central iuminary. The
lance from us Of Arcturus is
million times that of tue snn. aud
motion Of 1877 miles III a second mi
be continued for 700 years before
would be carried across a space IN M
heavens which to Il eyes wonid
no greater than the width of the nc
at the full" II
A new process for coating o q
steel consists in the use of II bath CO
sisting Of zinc. tin, and aluminium.
IS claimed that this produces q cog
ing which is much superior TO al
now known. adhering SO firmly To
the sheet will stand working after
has been applied and will resist corr
sion and can even be heated red e
without injuring it. The coating 4
applied III the same manner as III u
well-known process of galvanlxinS
that is, by dipping galvanized sheel
in the metal alloy. The most sf
proved mixture is made by meltiI
together 81 parts of zine, II parts /
tin, and II parts Of lead and o'5 of
part of aluminium. The process
patented.
An interesting paper on the effec'
of light at very low temperatures WI
| recently submitted to the Paris Acat
envy of Sciences by NM. Auguste an
Louis Lumiere. By using liquid a
they were able to obtain very 10
| temperatures, and when a sensitize
gelatino-bromide plate was immense
in it and exposed to light for a sho
time, no tint was shown on develoI
ment. When the plates were IN
mersed in the liquid air, but above
to regain their original t%emperatu1
without being exposed to the ligh
they did not show any changes J
their properties. Fl. however, plate
of great constituencies We're exposed
-l91 degrees Centigrade, they r
quired an exposure about fonr hui
bred times as long as at ordinary ter
peratures.
AS a motive power, the explosls
force Of liberated heat has, Of cours,
long been utilized, but it seems tn
to the ingenuity Of Rudolf Diesel,
Bavarian inventor, IA due the col
struction Of a practically avallab
heat motor. In this device. which
technically explained at much lengt
in the foreign scientific journals,
sharp distinction is made between tt
temperature of ignition and the ter
perature of combustion. The first
these is q constant value at each pre-
sure and dependent only on the ply
ical qualities of the fuel, the high'
the pressure the lower the temper,
ture of ignition. The temperature
combustion, on the other hand,
variable, depending on many conc
tons. and esnecially on the quality
the air by which the combustiCp
maintained, put is always higher tRt
the temperature Of ignition. Brief
Diesel's radical departure from
previous practice is defined as consis
ing in generating a combustion tel
perature by mechanical compressit
of pure air by ingeniously adapt
methods, utilizing this temperature
ignite the fuel, and by SO introducil
the fuel that the heat lost by expa
sion is practically balanced by Il
heat added by combustion.