Every evening, Wilmington daily commercial., 1921-07-28
Lighter Than Cork!
BY Frederic J. HAskin

Washington, July 2S.-A new exhibit
in the National Museum displays
samples of the lightest wood known
balsa.
A beam Of balsa yard long, three by
four inches thick is lying on the table.
You bend to pick it up, prepared for its
| lightness. Yet the sensation of finding
a beam of wood no heavier than fairly
heavy book takes you by surprise. 1t
recalls the fake weights which comedians
| left with so much elaborate effort in the
vaudeville skits. A tag says that the
beam weighs 1.6 pounds.
In the tropics where balsa grows
men carry long thick trunks OF balsa
| trees without the effort necessary IN
hauling other logs. Balsa is only about
| half as heavy as cork, which We regard
as a symbol of lightness.
Near the beam in the exhibit is a
box about q foot long and little less in
width This box, too, Is surprisingly
light But that is not its most interest,"
ing feature. Ii is an ice cream contalner.
The label explains that one quart OF ice
cream will remain firm in this box for
FIVE hours with an outside atmospheric
temperature of 15o. In other words, a
box of this wood is a sort of iceless re-
frigerator. This is due TO balsa S insulat-
ing properties.
When experts became in crested In
the commercial possibilities of balsa
they examined the cells and found them
to be barrel-shaped with very thin walls.
The soft porous structure of the wood
accounted for its hghtness and also
r.. a .x,.l Lott ar Sf
cold and against heat. 10 n test made
with fireless cooker contrlvance OF
balsa wood, food placed in the cooker at
night was still hot the next morning.
Facts learned by the various expert
ments are being put to practical use.
Balsa is being used extensively Tor re-
frigerator Innings on ships and for ice
boxes.
Wood Grows the Year Round.
Still another exhibit in the museum
is a cross section of log of balsa. The
wood is almost white and of n rather
silky texture. with lght-eolorcd bark.
The label calls attention TO the fact that
there are no annular rings such as our
temperate zone trees have. Here dur
ing the winter months new cells are not
filling out and thin film forms inside
The bark. In the spring cells grow out
side Of this film and the line remains
diitinct in cross section OF the wood TO
mark year in the life of the tree.
But in the tropics, except IN . few
places, there is no season of rest from
growing. The cells may grow irregularly,
swiftly in the RAINY seasons and not very
much in dry weather, but they are stead
ilv growing, so that the trees are un-
circled.
A few wears ago, balsa trees had no
commercial value. They were merely
known as tropical specimens used by the
natives of Central America for raft
material because of their ex-reme light
ness. The very name balsa is Spanish
for raft and was given 70 the wood by
Spanish explorers in America when they
noticed that the natives used II 50 much
for water travel A number Of people
could be safely floated on these rafts so
much lighter than cork, but If any fore
sighted business man thought of the
wood as q commercial possibility he soon
abandoned the idea when he saw how
quickly II decayed and how 1T gradually
became waterlogged.
But finally, a retired sea captain be-
came interested in hfe-saving apparatus. |
He recalled the remarkable rafts of balsa |
logs on which the na-ives of Central /
America rode end he wondered If some |
thing could not be done to the wood to /
preserve it and make it waterproof. /
He sent for some samples snd made a |
number of experiments but with no |
success.
Then he heard of a new wood preserv- |
ing process which had been patented |
and he got in touch with the inventor
By the process every duct and cell in a |
piece of wood could be costed with a |
thin water-proohng substance This |
method was tried out on balSa wood and |
it worked satisfactorily. The porous
wood was made durable and its useful |
possibilities instantly became numerous /
Since then, IT has been used In making 4
pontoons for hydroplanes, snd in |
making parts of airplanes where light, /
EASILY worked wood is desirable. Life |
RATS, and life boats are being
made of balsa as substitute for cork So /
ouovant is the wood that as many as 60 |
people can ride on some of the life RATS 1
Yet they do not take up much room on /
4 boat and number of them can be set I
afoat quickly IN an emergency.
BaIsa in the World War.
When the submarine mine barrage I
vas laid in the North Sea, $4,000 balSa
ioais were used. If was said TO be the I
,nly wood available, which could stand /
he exposure TO water and at the same /
ime resist the impact of death bombs.
Balsa is being used In time of peace
or buoys and surf boards and other
loating things, and even for making
arved TOYS, where its softness Is a desir-
bile feature. AS material for making
toppers for bottles it is replacing cork
o very small extent.