The reason why : $b a careful collection of many hundreds of reasons for things which, though generally believed, are imperfectly understood. A book of condensed scientific knowledge for the million — John Stuart Mill — John Shaqi
The reason why : $b a careful collection of many hundreds of reasons for things which, though generally believed, are imperfectly understood. A book of condensed scientific knowledge for the million
John Stuart Mill · en
The candles, gas, or fires that may be burning in the rooms where
people are assembled. Three candles produce as much carbonic acid gas
as one human being; and it is probable that one gas-light produces as
much carbonic acid gas as two persons.
24. _Have people ever been poisoned by their own breaths?_
In the reign of George the Second, the Rajah of Bengal took some
English prisoners in Calcutta, and put 146 of them into a place which
was called the "Black Hole." This place was only 18 feet square by 16
feet high, and ventilation was provided for only by two small grated
windows. _One hundred and twenty-three of the prisoners died in the
night_, and most of the survivors were afterwards carried off by putrid
fevers. Many other instances have occurred, but this one is the most
remarkable.
CHAPTER III.
25. _What is oxygen?_
Oxygen is one of the most widely diffused of the elementary substances.
It is a gaseous body.
[Verse: "Stand in awe and sin not: commune with your own heart upon
your bed and be still"--PSALM IV.]
26. _Why do persons who are walking, or riding upon horseback feel
warmer than when they are sitting still?_
Because as they breathe more rapidly, the combustion of the _carbon_
in the blood is increased by the _oxygen_ inhaled, and greater heat is
developed.
27. _Why does the fire burn more brightly when blown by a bellows?_
Because it receives, with every current of air, a fresh supply of
_oxygen_, which unites with the _carbon_ and _hydrogen_ of the coals,
causing more rapid combustion and increased heat.
28. _Why does not the oxygen of the air sometimes take fire?_
Because oxygen, _by itself_, is incombustible. The wick of a candle,
which retains the slightest spark, being immersed in oxygen, will
instantly burst into a brilliant flame; and even a piece of iron wire
made red-hot, and dipped in oxygen, will burn rapidly and brilliantly.
Oxygen, though non-combustible of itself, is the most powerful
_supporter of combustion_.
29. _Why do we know that oxygen will not burn of itself?_
Because when we immerse a burning substance into a jar of oxygen, it
immediately burns with intense brilliancy; but directly it is withdrawn
from the oxygen, the intensity of the flame diminishes, and the oxygen
which remains is _unaffected_.
30. _Why do we know that oxygen is necessary to our existence?_
Because animals placed in any kind of gas, or in any combination of
gases, where oxygen _does not exist_, die in a very short time.
31. _Where is oxygen found?_
It is found in the air, mixed with _nitrogen_; in water combined with
_hydrogen_; in the tissues of vegetables and animals; in our blood; and
in various compounds called, from the presence of oxygen, _oxides_.
32. _Why is the oxygen of the air mixed so largely with nitrogen?_