man, animals, plants, and nature's processes.

We now know that to continually

dump sewage or chemicals into a hody of water such as a lake may kill certain
small organisms,

or animals, which provide food and oxygen for larger

animals, and eventually fish, which a person might depend upon for his food
It is through examples like this we see that there are

or business,

“ecological chains" which, if broken, may result in the destruction of the
Nature, we have observed,

whole chain,

"likes" order and balance,

Within

nature are many "chains" which complement or supplement ecological patterns,
While the first example was how a chain could be disrupted by pollution, or
contamination,

such a chain can also transmit contamination,

factories. produce a waste chemical of mercury.

In some areas,

This waste is discharged into

The mercury is absorbed into the tissues of the smaller

a fresh water lake,

organisms and thus transmitted through the food chain until it reaches man,
If the concentrations or amounts of this chemical are large enough, the man
may become ill from mercury poisoning,

The same sort of thing can happen

with radioactive contamination or "pollution,"

At this point, it would be well to stop for a moment and recall what
happens when a nuclear explosion--especially a hydrogen bomb explosion--occurs,
If on the surface, the burst will lift up an incredible tonnage of material
into the atmosphere,

The gassy inferno fireball shoots upward surrounded by

Vapor and particles which roll and boil around it in a maelstrom of radio-

activity and turbulence at the cap of the "mushroom cloud."
The lower part of the cloud, or column, contains the heavier particles
of material

(soil,

water vapor,

rock)

which have been made radioactive,

part will be carried away by the winds in the lower atmosphere
sphere or zone in which is found most of our weather),

17

Cee 55028)

This

(the Tropo-

The heaviest particles

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