Perth Amboy evening news., 1921-07-28
LIGHTER THAN O
BY Frederic j. Haskin.

WASHINGTON, July ga new exhibit in
the National Museum displays samples of the
lightest wood ~known-balsa.
a beam of balsa a yard long, three by four
inches thick is lying on the table. You bend
TO pick it up, prepared for its Hghtness. Yet
the sensation of finding a beam of wood no
heavier than a fairly heavy book takes you by
surprise. 1t recalls the fake weights which
comedians lift with so much elaborate effort
in the vaudeville skits. A tag says that the
beam weighs lie pounds.
In the tropics where balso grows, men carry
long thick trunks OF balsa trees without the
effort necessary in hauling other logs. Balsa
10 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
a foot long and a little less in height and width.
This box, too, is surprisingly light. But that Is
not it's most interesting feature. 1t is an ice
cream container. The label explains that one
quart of ice cream will remain firm in this box
for five hours with an outside atmospheric tenn
perature of rs degrees. In other words, a box
of this wood is a sort OF iceless refrigerator.
This is due to balsa's insulating properties.
When experts became Interested in the COM
mercial 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 lightness and also
for its being a good i~nsulator against cold and
against heat. In a test made with a freless
cooker contrivance of balsa wood, food placed
in the cooker at night was still hot the next
morning.
Facts learned by the various experiments are
being put to practical use. Balsa is being used
extensively for refrigerator Innings on ships and
for ice boxes.
Wood Grows the Year Round.
Still another exhibit in the museum is a cross
section of a log of balsa. The wood is almost
white and of a rather silky texture. with light
colored bark. The label calls attention to the
fact that there are no annular rings such as
our temperate zone trees have. Here during
the winter months new cells are not filling out
and a thin film forms inside the bark. In the
spring cells grow outside of this film and the
line remains distinct in a cross section of the
wood to mark a year in the life of the tree.
But in the tropics, except in a 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 steadily growing, so that the trees
are uncircled.
A few years ago balsa tries had no COM
mercial value. They were merely known as
tropical specimens used by the natives of
Central America for raft material because OF
their extreme lightness. The very name balsa
Is Spanish for raft and was given to the wood
by Spanish explorers in America when tAey
noticed that the natives used it so much for
water travel. A number of people could be safely
floated on these rats so much lighter than cork,
but if any foresighted business man thought OF
the idea when he saw how quickly 1t
decayed and how it gradually became water
logged.
But finally a retired sea captain became in
in life-saving apparatus. He recalled
the remarkable RATS of balsa logs on which
the natives of Central Amreica rode and he
if something could not be done to
the wood to preserve it and make 1t waterproof.
He sent for some samples and made a number
of experiments, but with no success.
Then he heard Of a new wood preserving
process which had been patented and he got
N touch with the inventor, 10y. the ploceSs
every duct and cell In a piece of wood could
be coated with a thin water-prootng sub
stance. This method was tried out on baisa
wood and it worked satisfactorily. The porous
wood was made durable and it's useful posslblli-
instantly became numerous.
Since then it has been used in making pom.
toons for hydroplanes, and in making parts OF
where q light, easily worked wood is
Life preservers, RATS. and life boats
are being made of basa as a substitute Tor
cork. So buoyant is the wood that as many
as Sixty people can ride on some OF the NE
RATS. Yet they do not take up much room on
a boat and a number of them can be set atoat
quickly in an emergency.
Balsa in the World War.
When the submarine mine barrage was lald
in the North Sea, so, 900 balsa floats were used.
1t was said to be the only wood available, when
could stand the exposure to water ana at the
time resist the impact of death bombs. !
Balsa is being used in time of peace Tor buoys
and surf boards and other floating things, ana
even for making carved toys, where lts SOIL
ness is a desirable feature. AS a material for
making shoppers for bottles it is replacing cork
to q very small extent.
Because of it's varied uses balsa Is now re-
carded as an important product. Experts have
visited the American tropics to study the trees
in their native state. They report that palsa
is one of the swiftest growing trees, that IL
a year into a tree thirty-siX feet tall and about
FIVE inches in diameter. In five years a Tree
trunk averages nearly thirty inches across and
the tree will be from forty to sixty feet tall.
1t NAV not grow any taller than this, but the
trunk may reach five feet in thickness. Inc
leaves of the young balsa tree are very large,
sometimes three feet across.
The extreme lightness of balsa wood was
shown graphically when a block of balsa was
in weight with similar blocks of other
wood. A cubic foot of balsa weighed 9.3
pounds. Cork, the next lightest, was 1871
pounds, and from there on in round numbers
The weights ran through Missouri corkwood is,
spruce 81, hickory Sd, ebony ~, and queoracho'
the heaviest wood known: q.