Put a cup of cold water in a saucepan over the fire, and see
what happens. When it becomes so hot that we cannot bear
the fingers in it take the temperature. This is scalding hot
water. Soon tiny bubbles form on the edges and bottom of
the pan. This is the air in the water which expands by the
heat. These air bubbles disappear as they reach tlie colder
water near the top, and the cold water being heavier goes to
114 SCHOOL KITCHEN TEXTBOOK
the bottom. This makes a sUght motion in the water which
is called simmering, and which is often mistaken for boiling.
Water simmers at about 180° Fah.
After a while all the water is very hot, that nearer the
bottom is changed into steam, large bubbles of steam rise
rapidly and soon break above the surface, making quite a
commotion or bubbling all over the top, and we say "the
water boils."
We take the temperature, and find it boils at 212° Fah.
As the bubbles break the steam escapes, and when it comes
in contact with the cold air above and outside the kettle it is
changed, or condensed, into a fine mist. We call this mist
steam, but it is water vapor ; the real steam is invisible.
Thus we learn that boiling is the changing of water or liquid
into steam by the action of heat suflScient to cause commotion
or bubbling on the surface.
Any solid must first be melted into a liquid before it can
boil. We do not really boil our potatoes ; we cook them in
boiling water.
After boiling the water some time we take the temperature
again, and find the water is no hotter than 212° Fah. We
increase the fire to make the water boil faster, and the force
of the steam lifts the cover, and the water runs over and
spatters the stove ; but we find the water is no hotter. The
excess of heat escapes in the steam, and in ordinary kettles it
is impossible to retain the whole of it.
Cover the kettle, and some of the steam condenses into
water on the inside of the cover, drops back again into the
kettle, and gives up its heat. So although we do not gain any
greater degree of heat by boiling rapidly, yet by keeping the
cover on more of the heat is kept inside. The steam, as it
changes from a vapor to a liquid, gives back the heat that
it has, and by keeping in the steam we can economize
heat. The water does not evaporate so quickly when
covered.
We cool a portion of the boiling water, and find it tastes
flat. This is because the gases, or air, which gave it a fresh
taste have escaped.
If we let the water all boil away, or be changed into steam,
WATER 115
we find only a rim or deposit of brown scum on the edge of the
pan.
We learn by this experiment in cooking or boiling water —
That it boils at 212° Fah., or when it bubbles all over the
top;
That when once it boils all over it becomes no hotter, and
fuel and heat are wasted when it boils at a galloping rate ;
That the kettle should never be so full that the water, as it
expands in heating, will boil over ;
That it loses its freshness by long boiling, and should be
used at once ;
That it boils away faster if uncovered ;
That in time it will all evaporate and pass off as steam, and
more must be added as needed ;
And, lastly, that the water leaves a deposit on the kettle,
which, if not removed, will in time affect the taste of the water.
If water boils over, it clings to the outside and browns the
kettle.
Page 62
Presented as published in 1915. Historical recipes may not meet modern food-safety standards. Cook from the modern interpretation, not the original instructions.
AI-modernized reading of the original text
Put a cup of cold water in a saucepan over the fire, and see what happens. When it becomes so hot that we cannot bear the fingers in it take the temperature. This is scalding hot water. Soon tiny bubbles form on the edges and bottom of the pan. This is the air in the water which expands by the heat. These air bubbles disappear as they reach the colder water near the top, and the cold water being heavier goes to
the bottom. This makes a sUght motion in the water which is called simmering, and which is often mistaken for boiling. Water simmers at about 180° Fah.
After a while all the water is very hot, that nearer the bottom is changed into steam, large bubbles of steam rise rapidly and soon break above the surface, making quite a commotion or bubbling all over the top, and we say "the water boils."
We take the temperature, and find it boils at 212° Fah. As the bubbles break the steam escapes, and when it comes in contact with the cold air above and outside the kettle it is changed, or condensed, into a fine mist. We call this mist steam, but it is water vapor ; the real steam is invisible.
Thus we learn that boiling is the changing of water or liquid into steam by the action of heat sufficient to cause commotion or bubbling on the surface.
Any solid must first be melted into a liquid before it can boil. We do not really boil our potatoes ; we cook them in boiling water.
After boiling the water some time we take the temperature again, and find the water is no hotter than 212° Fah. We increase the fire to make the water boil faster, and the force of the steam lifts the cover, and the water runs over and spatters the stove ; but we find the water is no hotter. The excess of heat escapes in the steam, and in ordinary kettles it is impossible to retain the whole of it.
Cover the kettle, and some of the steam condenses into water on the inside of the cover, drops back again into the kettle, and gives up its heat. So although we do not gain any greater degree of heat by boiling rapidly, yet by keeping the cover on more of the heat is kept inside. The steam, as it changes from a vapor to a liquid, gives back the heat that it has, and by keeping in the steam we can economize heat. The water does not evaporate so quickly when covered.
We cool a portion of the boiling water, and find it tastes flat. This is because the gases, or air, which gave it a fresh taste have escaped.
If we let the water all boil away, or be changed into steam,
WATER 115
we find only a rim or deposit of brown scum on the edge of the pan.
We learn by this experiment in cooking or boiling water —
That it boils at 212° Fah., or when it bubbles all over the top;
That when once it boils all over it becomes no hotter, and fuel and heat are wasted when it boils at a galloping rate ;
That the kettle should never be so full that the water, as it expands in heating, will boil over ;
That it loses its freshness by long boiling, and should be used at once ;
That it boils away faster if uncovered ;
That in time it will all evaporate and pass off as steam, and more must be added as needed ;
And, lastly, that the water leaves a deposit on the kettle, which, if not removed, will in time affect the taste of the water.
If water boils over, it clings to the outside and browns the kettle.