The Pacific commercial advertiser. [volume] (Honolulu, Hawaiian Islands) 1885-1921, 1893-05-01
MAKING LIQUID AIR.
A SCIENTIST EXPLAINS HIS CHEM
IcAL DISCOVERIES.

Professor Dewar's Experiments May Prove
to BE the Greatest Investigations of the
Century-PoverfuI Gases Reduced to a
Fluid State.
The Pail Mall Budget of London pub
Eshed an interview with Professor James
Dewar on what is represented as being
a great scientific discovery" that OF
I making liquid air Introductory TO the
interview the article says that his hq-
uefactions of permanent gases and the
use of wanna to preserve great cold mark
one Of the most important chemical dis
coveries of the century," 1t is held by
scientists that any gas may be hquefied
| if the pressure and cold may be obtained
| and a vessel OF sufficient strength TO
/ Withstand the great pressures.
! OF the gases that may be Hquefed car
/ bonic ACID gas has been found to be the
| cheapest and readiest made, and while it
! has been known for many years that it
could be liquified it has generally been
so prepared only in small quantities for
scientific uses. The use of compressed
air as motive power has presented many
difficulties, the principal one being its
bulkiness; hence large vessels must be
used in order to get a sufficient amount
Of motive power. and it is hard to make
these strong enough and ut the same time
light in weight.
AS n motive power it Is used at pres
sure Of from GOO to 800 pounds. But if
Professor Dewar has discovered an eco
nomical and ready way of iquefying it.
it Will tend to solve Il problem in carry
ing motive power in storage bulk that
will he of great benefit to the students in
this line. In the talk with the represent
ative of The Pail Mall Budget, tie says:
"Well, | don't think there's very much
to say, because I've told all have to tell
about the matter In my two lectures.
but l do believe there's a great deal more
to be learned about the subject. You
see, at present we've got these gases down
to 210 degrees below zero, and the lowest
possible temperature is PA degrees be-
low. If we could get some 80 degrees
lower down. we might liquefy hydrogen
Hydrogen has never been liquetied in a
free state yet.
Now, it's Il strange thing that air can
be made into a homogeneous Guid You
would think, as oxygen can be !iquefied
at -182 degrees and nitrogen rot until
-192 degrees, that as you made the air
colder and colder the oxygen would be.
come liquid first and then the nitrogen
saw that prediction made III stand
ard work only the other day i,nw.
dare say. you will ask why the oxygen
don't come down first
Stepping quickly back to the desk Pro
fessor Dewar took up pencil and began
to draw with rapid strokes on the back
of a letter, The diagram when it was
finished looked more like the law OF d.
minishing returns turned up on one side
than anything else that ain acquainted
with. While he drew he rapidly ex-
planned how the influence of atmospheric
pressure on the different volumes of nj
trogen and oxygen in air makes them
boil almost exactly at the same tempera-
ture. as he made each point he frOwned
a little, drawing up the wrinkles between
his eyes. Now, that, in the old theo
logical days, would have been taken as
a providential dispensation The strange
thing is that when liquid air evaporates
again they are under the same pressure
and the nitrogen goes off first as you |
would expect.
Ozone can be Equefed by acting on |
the vapor given off from liquid oxygen |
by electricity, 1t is splendid dark blue |
color, almost as dark as indigo. Ozone |
has not the same inolecule as oxygen. |
and the electricity breaks up three tWos |
into two threes That is the secret of ii |
The queer thing about liquid ozone is |
that when it goes back into gas again it |
explodes. You wouldn't think it, but ii
is stronger than dynamite as an explo-
siye. It's simply because the ozone goes
back into the molecular form of oxygen
so fast. The force that comes from the
makes it explode without
meeting with any outside body It's a
explosive.
I'VE have discovered that liquid oxy-
gen acts as lens 1t is so transparent
to heat, so to speak, that even at 1872
degrees below zero you can focus heat
on it from one side and light piece of
paper by it on the other. You know
that's just what happens III the earth.
The suns heat gets focused on to the
earth through the lens formed by the
vacuum Of space, which is SO cold that it
hasn't any temperature at all--absolute-
ly zero"
Professor Dewar gave a lecture on
Liquid Air" at the Royal institution in
the presence of the Prince of Wales, tho
Duke of York, Lord Salisbury and other
notable persons. He showed that by the
of heat the air is converted
INTO a liquid with total loss of chemical
incapable of supporting COM
bustion, or of entering into combination
even with phosphorus and sodium, while
certain physical properties remain. The
of oxygen into ozone was also
described, and the retention by oxygen
Of its peculiar optical properties at the
lowest temperature was demonstrated
by the very dense and we'll defined bands
Of its spectrum In ordinary conditions
oxygen shows no unreasonable thermal
absorption. but at low temperature its
thermal absorptive power becomes mani
fest.