Evening star., 1934-06-14
THIS AND THAT
BY CHARLES Z. TRAcEWELL.

! through the bubbles in q fashion
vastly reminding the spectator of o
small boy showing of his diving
prowess at the ole swimmin' hole.
The rosy barbs, silver -glistening
cousins of the goldhshes, are not In
the least afraid of the air stream.
They do not, however, move through
1t as consistently as the fishes already
named. They make no sport Of 1t,
but 60 about their regular business;
II they get in the bubbles, they do
not mind, and II they do not get In
them. they do not mind. They are in
different.
So much canont be said for the
angel fishes. perennial favorites Of
home aquarium enthusiasts. These
royal fellows are bit afraid OF the
bubbles, at their first encounter, but In
q short time lose any small fright
they may have had. They never,
however, indulge in the game Of run
ming the bubbles, as 1t might be called
These are very intelligent fishes, so
it Is not to be wondered at that after
awhile they come to realize that the
rising stream of bubbles Is good for
them. Although they probably do not
connect the decrease Of their gasping.
under the influence Of the carbon
dioxide In their tank, with the stream
of bubbles, which finally blows this
harmful gas cut Of the water, there
can be no doubt that they group
around the stream Of air and remain
there.
A favorite pose Of the angel fish is
to stand with its tail just in the edge
Of the stream of bubbles.
Another and more often assumed
pose. Is with head about an inch from
the outer limit of the air stream.
One might think, offhand, that the
humble but beautiful goldfish, a fav-
orite in a million homes, would love to
dash through the air bubbles, but 1t
does not, it prefers to ignore them.
Perhaps this variety of attitudes is
enough to show that there is never
any telling how q fish will greet the
introduction of so novel a thing into
its tank as a stream Of air, forced
up from the bottom.
In nature, in her pools and streams,
air Is never introduced in any such
fashion. She oxygenates her water
by running the surface, by exposure of
that surface to all the fresh air there
is, and by the action of growing water
plants.
The problem of getting rid of the
carbon dioxide, given of as a waste
product by the vtrtebrates, is no prob
lem at all. in nature, owing to the
immense saturation which Is achieved
even in the smallest pool. which will
be q million times as large as an in
door aquarium.
The fish confronted with a stream
of air is meeting something absolutely
new in his experience.
The fact that he soon comes to
accept it for the best speaks volumes
for the adaptability of these creatures.
The nearest approach to it. for
mankind, lies in the jets of air which
are blown upward at certain conces-
sionS in amusement parks and on
piers at Summer resorts. But this
device Is merely air in air.
The fishes shower bath" Is air
through water, the bubble rising, not
falling.
1t must be ar unusual experience
for q fish. The only phenomenon in
nature which approaches it is the single
stream Of practically pure oxygen bub-
bles which certain underwater plants
give of upon exposure to strong sun
shine. There is behind them. how
ever, no pressure giving artificial
strength to their upward movement.
Even the fishes learn that man Is al
vavs I'M to tricks