     Going through the paper this morning, I came on a story that said that 
a large urban development in the New Jersey meadows near New York City 
would not upset the ecology of the region.  A few pages further on I came 
on another story that said that the importation of tropical fish into 
Florida, where many of them escaped into the local waterways, was upsetting 
the ecology of the area.  There was another story about an oil spill; and 
still another about the development of a car that would not pollute the 
air.  On the editorial page, both the cartoon and the lead editorial urged 
the development of exhaust-free automobiles as soon as possible; if not, 
they warned, we wouldn't have to worry about ecology at all any more.
     Ecology is the branch of science which deals with the balance between 
living things and their natural environment; as it was used in the news-
paper stories that I had been reading, it referred to the balance of nature 
itself.  It is something that everyone is concerned with nowadays because 
we've suddenly awakened to find that man is destroying the balance of 
nature more rapidly than nature can repair the damage.  The wastes from our 
factories, from our automobiles, from our airplanes, from our power plants 
are polluting our lakes and rivers, the soil of our farms, the animals who 
share the earth with us, and even the great oceans and the air we breathe.  
We face a great danger to our world, and we have discovered it at the 
eleventh hour.
     Let's take some examples.  The industrial cities on the Great Lakes 
pour out their wastes into the streams that run into the lakes.  One, of 
these streams, the Guyahoga River that goes through Cleveland, Ohio is so 
filled with oil that it is a fire hazard!  Think of that--a river that 
can catch on fire, indeed that has caught on fire!  Many of the wastes that 
run into the lakes are rich in the foods that are used by algae, plants 
that live in the water; they become too well fed.  As they multiply and 
then die, they choke off the oxygen which is needed by the fish and other 
living things in the lakes.  The great Lakes are dying, in other words; 
their waters are polluted and fewer and fewer forms of life can survive in 
them.
     Another killer that we release in the water is oil.  A huge tanker 
broke up off the south coast of England.  Not only did it dirty the 
beaches, some of the best in England, but it caused the death of thousands 
of birds and fish.  The birds, their feathers coated with oil so that they 
could not fly, were a particularly sad sight.  Many people tried to clean 
the oil from the birds, but many of them were beyond saving.  A similar 
disaster occurred when an off-shore oil well spilled thousands of gallons 
of oil into the Santa Barbara Channel, off the coast of California.
     California, with its rapid growth and its millions of automobiles, has 
had some particularly bad problems with air pollution.  In fact, the word 
"smog" was coined to describe the combination of smoke and fog which often 
fills the air over Los Angeles to the extent that the eyes hurt and brea-
thing becomes difficult.  The word may come from Los Angeles, but the con-
dition is familiar to such other cities as Tokyo, Mexico City, Dusseldorf, 
and London.  The chief cause of smog is the exhaust from cars and smoke 
from factory chimneys or apartment house incinerators.  When you fly over 
any large city nowadays, you are aware of the dirty haze that hangs over it 
-- and into which you must descend.
     But what to do about it?  Give up automobiles and airplanes?  Give up 
electricity (for power plants are major sources of air pollution)?  Give up 
factories?  None of these seems very probable; yet it is necessary to cut 
the amount of pollution in the air or the earth may become uninhabitable.  
People have already died when smog has settled too long and too thickly 
over one area.  Some scientists believe that the haze in the air is block-
ing out some of the heat from the sun, and that may cause great changes in 
the climate.  Perhaps we are bringing a new Ice Age upon ourselves.
     DDT seemed to be one of man's great success stories.  DDT is an 
insecticide, a chemical used for killing insects.  It first came into wide 
use about the time of World War II.  It promised to bring two of mankind's 
most dreaded diseases, typhus and malaria, under control because it killed 
the insects that carried those diseases.  It was part of the "green 
revolution" in the United States; it was used to spray the fields and kill 
the insects that might damage the growing crops.  The huge agricultural 
production of the united States was in part due to this new protection 
against insects.  An enormous part of the earth's surface was sprayed with 
DDT at one time or another.
     After a few years, however, the first notes of warning were sounded.  
Wonderful as DDT was, it was also doing harm.  One of the most dramatic 
warnings came from the American naturalist Rachel Carson in a book called 
The Silent Spring.  She warned that a day might come when there would be no 
more birds because DDT was killing the insects which were the natural food 
of the birds.  By changing one part of the natural environment, we were, 
without realizing it, causing other changes to take place--and we might 
not find these changes desirable.  When her book appeared, most people did 
not take Miss Carson's warning too seriously.  The good that DDT was doing 
was too apparent; its bad effects had not yet become evident.
     Now, however, no one is inclined any more to say that she was seeing 
danger where there was none to see.  The effects of DDT have been dis-
covered in the last few years to be even more damaging than she predicted.
     In nature, there is usually a natural balance between living things.  
One kind of insect will keep another from becoming too common by using the 
first one as food; or the birds will help to keep the insect population 
from growing too large.  Other kinds of animals will keep the birds from 
multiplying too rapidly.  All this natural balance of one life form against 
another is endangered in the places where DDT has been used too much 
because the natural food supply has been changed or destroyed.
     But DDT has had another unexpected effect.  Many chemicals break down 
into their different elements very quickly.  DDT is not one of these.  When 
it enters into the "food chain," it can be passed along from one plant or 
animal to another without disappearing or breaking down into less harmful 
chemicals.  Cows feeding on grass that has been sprayed with DDT take 
some of it into their systems, and they pass it along to us in their milk:  
And remember that DDT is a poison.
     The most widely publicized example of DDT'S toxic, or poisonous, 
effect is on birds.  Many birds have taken in large amounts of the insecti-
cide.  The eggs that are laid by some of these birds have shells that are 
thinner than normal.  Many of the eggs are broken or do not develop, so 
that some species, or kinds, of birds are in danger of not being able to 
reproduce themselves.  We may indeed some day have a silent spring, without 
the familiar songs of the birds.
     The dangers of DDT have become so well known that it is now against 
the law to use it in many places.  But what substitutes are taking its 
place, and what will they do to our environment?  We don't really know.
     The chemical effect of DDT was to kill insects; it also had 
side-effects other than those for which it was used.  Aspirin, to take a 
familiar chemical, has the effect of stopping pain; with many people, 
however, it has the side-effect of inducing nausea of stomach disorder.  We 
have often rushed in with chemicals and processes or engineering projects 
which were intended to have particular effects.  But almost as often we 
have not waited long enough to find out what their side-effects would turn 
out to be.  And often enough they have turned out to be harmful.
     The ecological picture isn't one of total disaster, though it will 
take centuries perhaps to make sure that we can live on our own earth with-
out destroying ourselves and the other living things that share our world 
with us.  Probably the most hopeful part of the ecological picture is that 
people throughout the world are aroused to the problem.  The word ecology 
is no longer unfamiliar; it occurs frequently on the pages of newspapers, 
on the radio and television, in magazine articles.  When I was in college, 
not so many years ago, ecology was a very specialized branch of biology; in 
fact, I had never heard the term before I went to college--and I forgot 
it for a good many years thereafter.
     When the people become aware of a problem, and further, aroused by it, 
government and industry are much more apt to take action.  A new power 
generating plant is being considered for New York, for example.  A few 
years ago the major considerations would have been cost, location, and 
capacity.  Nowadays, however, another factor is sure to be discussed--what 
the plant will do to the environment.  What kind of fuel will it use?  
How much pollution will waste from that fuel add to the air and the water?  
Will the plant heat up the water surrounding it so that fish will be 
endangered?  Are all possible steps being taken to cut down pollution from 
the plant?  All these questions will be publicly debated, and the harmful 
effects of the proposed plant will be weighed against the benefits that it 
will bring.