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Teacher
Edition Contents
Skill,
Tools, & Craftsmanship
Cutting
& Drying Fish
Sharpening
Nails,
Pegs, & Lashings
Falling
Trees &
Small-Scale
Logging
Guns
Chainsaw
Clutch & Chain
Ice
Pick
Shelters
Wood
Stoves
Wall
Tents
Steambaths
Insulation
& Vapor Barriers
Gas
Lamps & Gas Stoves
Travel
Piloting
A Boat
Boat
Design
Magnetos
& Spark Plugs
Carburetors
Compression
Outboard
Motor Lower Unit
Outboard
Motor Cooling System
Dogsleds
Snowmachine
Tracks
Snowmachine
Clutch
Snowshoes
Winter
Trails
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Activities
- Put a little (room temperature) gas lamp fuel in your hand.
Blow on it. Does it feel cold? Why? Put a little room temperature
stoveoil in your hand. Blow on it. Does it feel as cold? Why?
Can you explain why we don’t use stoveoil in a gas lamp?
Be careful. The fuel is volatile. Yes it feels cold. The fuel
is evaporating. Stove oil doesn’t feel as cold as it doesn’t
evaporate easily.
- Cut two identical blocks of wood. Split one into four parts.
Split the other into small kindling. Make two campfires of the
same size. Put the split pieces of the first block on one and
the split pieces of the second on the other. Which burns faster?
How much faster? What can you say about increasing the surface
area of fuel?
The fire made of the finely split pieces will burn much faster.
- First light an old gas lamp. Let it cool down, then take the
generator out. If you are careful you can do it without breaking
the mantle. Is it black with soot? Scrape it clean with a pocket
knife or sandpaper. Reinstall it, and light the lamp again. Can
you tell the difference between before and after? What is the
difference and why?
The clean generator will burn much brighter than the dirty
one. The soot on the dirty one insulated the fuel from the flame.
- Observe. What do you suppose the little needle is for on the
end of the generator you just removed?
It cleans the tiny hole through which the fuel passes. If
the hole is plugged, fuel cannot get through to the flame.
- Get someone with the necessary knowledge to show you how to
replace a mantle. While the old mantle is off, inspect the screen.
Does it have any holes?
- If possible, research what kind of material is used in the
mantle of a gas lamp. How is the material unique?
I used to know the answer to this, but they have changed the
material. The uniqueness comes in that the remaining ash which
is the mantle, glows when heated. It’s electrons jump to
higher orbits when excited by the heat, but when they collapse
to their natural electron orbits, the emit photons of light.
- Pump the tank full of pressure. Release the pressure. Lubricate
the pump with a few drops of oil, and pump the tank again. Is
there a difference? Why?
A lubricated pump is better because it has less friction,
but the oil also serves to seal the plunger in the pump.
- Ask people in your village if they use gas lamps outdoors in
the past. Do they still use them in hunting, whaling, or fishcamps?
- Light a gas stove. Identify the parts of the flame that are
producing carbon dioxide. Identify the parts of the flame that
are producing carbon monoxide.
Yellow flame is carbon monoxide, blue is carbon dioxide.
- With the same amount of water at the same temperature in the
same teapot, time how long it takes to boil water on the gas stove,
on a propane stove, and on an electric stove. Which is faster?
Which do you think is more convenient? Which do you think is safer
in the house?
The gas stove gives the most intense heat, but it is messy
to fill and inconvenient to use.
- With pliers, hold a piece of a broken mantle in the flame of
a candle or gas stove. Does it glow?
Yes it does. Even the string glows.
Student Response
- What are the three main parts of a gas lamp?
Tank, generator, and mantle
- What is the main purpose of the generator?
Heating the fuel and air
- What happens to fuel in the generator?
It turns to a vapor
- Draw a picture of fuel as a liquid and the same amount of fuel
as a vapor.
Drops of liquid are big, drops of vapor are small but more
numerous
- Why does the generator pass over the flame in both the gas
lamp and gas stove?
When the fuel is heated, it turns to a vapor. If this didn’t
occur, the fuel wouldn’t burn well at all
- The screen in a gas lamp does two things. What are they?
Spreads the fuel and air mixture. Retains heat
- Why do whitefish hunters have a hard time with their gas lamps
in cold temperatures and what is the cure?
The cold air cools the generator too much and the fuel isn’t
vaporized. The cure is to put the glass on the lamp. This keeps
the heat in and allows the fuel to do its job.
- What color is the flame when carbon monoxide is produced? What
color is the flame when carbon dioxide is produced?
Yellow. Blue
- Which is more efficient in the production of heat, combustion
to carbon monoxide or combustion to carbon dioxide? By what ratio?
Carbon dioxide is more efficient. 1 to 3
Math
- If a blue propane flame gives off 1500BTU2 how many BTU are
given off if the air adjustment is wrong and the flame is completely
yellow?
500
- A 5-gallon can of Blazo fuel costs $38. It lasts Mark 3 months
in his trapping cabin. A bottle of propane lasts him 7 months
at home. Propane is $105. Which is cheaper per month?
Blazo is $12.66 per month; propane is $15 per month
- Gas lamps don’t work well with leaded gas. But Blazo fuel
is $8 a gallon, and leaded gas is $2.25 a gallon. New generators
are $1.98 apiece. Mark is wondering if it is cheaper to burn cheaper
fuel and change generators once a week or whether it is cheaper
to burn the correct fuel. Which method is cheaper if a gallon
of fuel lasts three weeks?
Blazo is $8. Gas plus new generators is $8.19. It isn’t
worth the bother. Burn blazo.
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