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
It has parted with about one-sixth of its oxygen, and taken up an
equivalent of carbonic acid. And were the same air to be breathed six
times successively, it would have parted with _all_ its oxygen, and
could no longer sustain life.
[Verse: "A prudent man forseeth the evil, and hideth himself; but
the simple pass on, and are punished."--PROVERBS XXVII.]
14. _Is the impure air sent out of the lungs lighter or heavier than
common air?_
At first, being rarefied by warmth, it is _lighter_. But, if
undisturbed, it would become _heavier_ as it cooled, and would descend.
15. _Why is it proper to have beds raised about two feet from the
ground?_
Because at night, the bed-room being closed, the breath of the sleeper
impregnates the air of the room with carbonic acid gas, which,
descending, lies in its greatest density near to the floor.
16. _What are the chief sources of carbonic acid gas?_
The vegetable kingdom (as will be hereafter explained), the combustion
of substances composed chiefly of carbon, the breathing of animals, and
the decomposition of carbonic compounds.
17. _Is breathing a kind of combustion?_
It is. In the breathing of animals, the burning of coals, or of wood,
or candles, &c., similar changes occur. The _oxygen_ of the air
combines with the _carbon_ of the substance said to be burnt, and forms
_carbonic acid gas_, which unfits the air for the purposes of either
breathing or of burning, until it has been renewed by admixture with
the air.
18. _What is carbon?_
It is one of the elementary bodies, and is very abundant throughout
nature. It abounds mostly in vegetable substances, but is also
contained in animal bodies, and in minerals. The form in which it is
most familiar to us is that of _charcoal_, which is carbon almost pure.
19. _What is meant by an elementary body?_
An elementary body is one of those substances in which chemistry is
unable to discover more than one constituent. For instance, the chemist
finds that water is composed of _oxygen_ and _hydrogen_. Water is
therefore a _compound_ body. But _carbon_ consists of _carbon only_,
and therefore it is called a simple, or elementary body.
[Verse: "Where no wood is, there the fire goeth out: so where there
is no tale-bearer, the strife ceaseth."--PROVERBS XXVI.]
20. _Why is it dangerous to burn charcoal in rooms?_
Because, being composed of _carbon_ that is nearly pure, its combustion
gives off a large amount of _carbonic acid gas_.
21. _What is the effect of carbonic acid gas upon the human system?_
It induces drowsiness and stupor, which, if not relieved by
ventilation, would speedily cause death.
22. _What is the reason that people feel drowsy in crowded rooms?_
Because the large amount of carbonic acid gas given off with the
breaths of the people, makes the air poisonous and oppressive.
23. _What other causes of drowsiness are there?_