There is now on the market a combination of a gas stove
and a fireless cooker which is convenient. The range can
always be used as an ordinary gas stove, but over some of
the top burners are hung cylinders which may be lowered
at will to cover the kettle which has been heating over the
burner. At the same time, the flame is extinguished by the
automatic turning off of the gas. The oven, too, is excep-
tionally well insulated and may be used as a fireless cooker
also. While the first cost of these stoves is more than that
of the ordinary types of ranges, they are undoubtedly
great savers of gas.
A thermos bottle uses the same principle as a fireless
cooker. Since heat cannot pass in any more readily than
it can pass out, both may be used to keep cold drinks cold
by protecting them from the heat of the air. Thermos
bottles are made with a vacuum between the inner and
outer layers, and are more resistent to the passage of heat
than the ordinary cookers.
Ice-boxes and refrigerators, too, are efficient in the meas-
ure in which they are non-conductors of heat, this depend-
ing on the kind and number of layers of material used for
"packing." Some people recommend the wrapping of the
ice in the ice-box in paper of some heavy material to keep it
from melting so fast by protecting it from the heat of the
air inside the box. This must not be done if it checks the
melting too much, for it is the melting of the ice which
causes the low temperature in the box, and the lowering
of the temperature is in proportion to the melting, the heat
of the air being rendered latent as the ice changes to water.
REFERENCES
Any good school textbook in Physics on heat.
U. S. Dept. of Agriculture. Farmers' Bulletin No. 298, "The Fire-
less Cooker."
118 FOOD STUDY
U. S. Dept. of Commerce. Bureau of Standards, Circular No. 55,
sections on Radiation, Refrigeration, and Ice.
QUESTIONS
1. Is the iron used for the top of stoves a good or bad conductor of
heat ? Does this matter in cooking ?
2. Why can you hold your hand for a few moments in an oven
whose temperature is above that of boiling water ?
3. How are steam and hot water radiators usually finished?
Why?
4. Which boils more quickly, a new tin kettle or one which is dull
on the bottom ?
5. Describe different types of fireless cookers.
6. Why are the metal bails on cooking vessels often made with
wooden handles ?
7. What was the old-fashioned tea cosey and how did it work ?
8. What are the materials commonly used in making ice-boxes ?
9. Why is the ice compartment at the top instead of the bottom
of an ice-chest ?
10. How may the weight of a piece of ice be determined by its
measurements in inches ?
XXII
CONVECTION OF HEAT
BROILED BACON
POTATO SALAD
A. How HEAT PASSES FROM ONE PLACE TO ANOTHER.
1. Convection of heat.
Put cocoa shells or sawdust into water and heat — in
a glass beaker if you have it. Notice the movement
of the particles. Does this indicate movement of the
water also ?
HOT-WATER SYSTEMS 119
B. PREPARE POTATO SALAD.
Use one potato. Serve with a crisp slice of bacon.
Explain carefully exactly how the heat in cooking passes
from the fire to the potato : to the bacon.
POTATO SALAD. ✪ Broiled Bacon
Food study
1917Page 60 · 2 recipe records on this page
Presented as published in 1917. 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
There is now on the market a combination of a gas stove and a fireless cooker which is convenient. The range can always be used as an ordinary gas stove, but over some of the top burners are hung cylinders which may be lowered at will to cover the kettle which has been heating over the burner. At the same time, the flame is extinguished by the automatic turning off of the gas. The oven, too, is exceptionally well insulated and may be used as a fireless cooker also. While the first cost of these stoves is more than that of the ordinary types of ranges, they are undoubtedly great savers of gas.
A thermos bottle uses the same principle as a fireless cooker. Since heat cannot pass in any more readily than it can pass out, both may be used to keep cold drinks cold by protecting them from the heat of the air. Thermos bottles are made with a vacuum between the inner and outer layers, and are more resistent to the passage of heat than the ordinary cookers.
Ice-boxes and refrigerators, too, are efficient in the measure in which they are non-conductors of heat, this depending on the kind and number of layers of material used for "packing." Some people recommend the wrapping of the ice in the ice-box in paper of some heavy material to keep it from melting so fast by protecting it from the heat of the air inside the box. This must not be done if it checks the melting too much, for it is the melting of the ice which causes the low temperature in the box, and the lowering of the temperature is in proportion to the melting, the heat of the air being rendered latent as the ice changes to water.
Any good school textbook in Physics on heat. U. S. Dept. of Agriculture. Farmers' Bulletin No. 298, "The Fireless Cooker."
U. S. Dept. of Commerce. Bureau of Standards, Circular No. 55, sections on Radiation, Refrigeration, and Ice.
1. Is the iron used for the top of stoves a good or bad conductor of heat ? Does this matter in cooking ?
2. Why can you hold your hand for a few moments in an oven whose temperature is above that of boiling water ?
3. How are steam and hot water radiators usually finished? Why?
4. Which boils more quickly, a new tin kettle or one which is dull on the bottom ?
5. Describe different types of fireless cookers.
6. Why are the metal bails on cooking vessels often made with wooden handles ?
7. What was the old-fashioned tea cosey and how did it work ?
8. What are the materials commonly used in making ice-boxes ?
9. Why is the ice compartment at the top instead of the bottom of an ice-chest ?
10. How may the weight of a piece of ice be determined by its measurements in inches ?
CONVECTION OF HEAT
BROILED BACON POTATO SALAD
A. How HEAT PASSES FROM ONE PLACE TO ANOTHER.
1. Convection of heat.
Put cocoa shells or sawdust into water and heat — in a glass beaker if you have it. Notice the movement of the particles. Does this indicate movement of the water also ?
HOT-WATER SYSTEMS 119
B. PREPARE POTATO SALAD.
Use one potato. Serve with a crisp slice of bacon. Explain carefully exactly how the heat in cooking passes from the fire to the potato : to the bacon.
POTATO SALAD.
Records on this page
Broiled BaconPotato Salad