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
Because heat, _entering into the lower portions_ of the water,
_expands_ it; the heated portions are then _specifically lighter_ than
those that are cooler; the hot water therefore _rises upward, and
forces the cooler water down_.
754. _What proportion of the earth's surface is covered with water?_
There are about one hundred and forty seven millions of square miles of
_water_, to forty-nine and a half millions of square miles of _land_.
755. _What is the amount of water pressure?_
The pressure of the sea, at the depth of 1,100 yards, is equal to
15,000 lbs. _to the square inch_.
[Verse: "But the land, whither ye go to possess it, is a land of
hills and valleys, and drinketh water of the rain of heaven."--DEUT.
XI.]
756. _What element is the most abundant in nature?_
_Oxygen_, which forms so large a part of _water_. Of animal substances,
_oxygen_ forms _three-fourths_; of _vegetable substances_ it forms
_four-fifths_; of _mineral substances_ it forms _one-half_; it forms
_eight-ninths_ of the _waters_ and _one-fifth_ of the _atmosphere_; and
aggregating the whole creation, from _one-half to two-thirds_ consists
of _oxygen_.
757. _In what ways does man use oxygen?_
Man _eats_, _drinks_, _breathes_, and _burns_ it, in various
proportions and combinations. It is estimated that _the human race_
consume in those various ways 1,000,000,000 lbs. daily; that the _lower
animals_ consume double that amount; and that, in the varied works of
nature, no less than 8,000,000,000 lbs. of _oxygen_ are used _daily_.
758. _Why does water dissolve various substances?_
Because the _atoms of water_ are very minute; they therefore _permeate
the pores_, or spaces, between the atoms of those bodies, and
_overcoming their attraction for each other_, cause them to separate.
759. _Why does hot water dissolve substances more readily than cold?_
Because the _heat assists to repel the particles_ of the substance
undergoing solution, and _gives the water a freer passage_ between the
atoms.
760. _Why is pump water sometimes hard?_
Because, in passing through the earth, it has become impregnated with
mineral matters, usually the _sulphate_ and _carbonate of lime_.
761. _Why is rain water soft?_
Because it is derived from vapours which, in ascending to the clouds,
_could not bear up the mineral waters with them_. It therefore became
purified or distilled.
762. _Why do kettles become encrusted with stony deposits?_
Because that portion of the water which is driven off in steam _leaves
the mineral matters behind_; they therefore form a crust around the
sides of the kettle.
[Verse: "He gathereth the waters of the sea together as an heap; he
layeth up the depth in storehouses."--PSALM XXXIII.]
It is said that if a child's marble be placed in a kettle, it will
attract the earthy particles, and prevent the encrusting of the
sides of the vessel.
763. _Why is it difficult to wash in hard water?_