Re: Fire (pine knots)

Lee Olsen:
Mario Petrinovich:
deowll:
Actually the myth busters managed to start a fire with a rounded lump
of
ice about the size of a person's head. A drop simply won't collect
enough light to do jack.

It would, be sure.

Water drop testing.

Could a monkey or some other animal (Pleistocene Homo for instance)
start a fire by chance simply having sunlight focus through a drop of
water suspended on a hair in the proximity of pitch or some other dry
material?

Glass bottles laying in dry grass have been known to start fires. The
bottom of a coke can polished to a shine with tooth paste can focus
sunlight enough to get a fire started with dry tinder. I've seen
numerous survival-type people start fires with various combinations of
sticks; however, I have yet to see this type of fire started without
first blowing on the hot coal after igniting the tinder material. This
means a combination of wind, water drop held at the correct distance
long enough, along with the right tinder in order for the process to
succeed.

To test the water drop hypothesis, pine pitch has been suggested for
tinder. I happened to have some pine pitch that I gathered for the
purpose of testing its qualities as mastic for attaching arrowheads to
a shaft (it works great).

Materials and methods.

A few of the tools used in this experiment.
http://tinyurl.com/kyx5s


The focal length of the magnifying glass was approximately 7 inches. As
soon as the light was pinpointed on the paper, it burst into smoke
within a few seconds and coals rapidly burnt a hole in the paper.
http://tinyurl.com/hjp8h
Paper with hole burned in it ignited by the 80mm diameter magnifying
glass. Also in the photo is one of the lumps of pine pitch.

Surprisingly, the same method would not light the pitch. It simply
smoked and blistered the pitch as it evaporated, reminding me of the
Wicked Witch of the West in Oz after Dorothy threw a bucket of water on
her.
http://tinyurl.com/ksbsv

No matter how long the glass was applied to the pitch, I could not get
a coal or fire going. I tried several different lumps of pitch just to
make sure the first one wasn't defective in some way.
http://tinyurl.com/g3hd5
A match finally did the trick and reduced the lump of pitch into a
small cinder pile.

Next I tried focusing sunlight through a drop of water suspended on
various items with little success. Gravity seemed to mess up almost
every attempt at some point, mostly wetting the paper rather than
burning it. Using a hair I finally did manage to hold a drop in
place long enough to concentrate sunlight on a piece of paper, but at a
very close distance, something around two or three millimeters focal
length. No smoke could be produced in this manner. Next I tried
focusing the spot of light on my arm. I could feel no warmth at all. If
the ignition point of pitch was higher than paper there was no point in
trying to light the pitch with heat so low I could not detect it on my
arm.

My conclusion is that a drop of water could never kindle a fire using
pitch or anything else, either deliberately or by chance.

Never-the-less, it happens every year, after first shower, in
savanna.
At Mediterranean it is hot, very hot. Thankfully shore breeze cools
it just enough for us to feel extremly comfortable in that environment. But
inland it is still very hot, and sunbeams are very strong.
Try to find something about pyrophytes. As I wrote, those plants
work that way. They need fire. And they are producing fire. Even without any
additional help. If you take a look at where those mediterranean pyrophytes
grow, they grow with the right metereological condition, which includes dry
summer, in regions of subtropical highs, where there are not many clouds.
What produces fire for those plants is pitch (resin), highly
combustible. As I wrote, this isn't so much exposed, naturaly. But a monkey
can help to expose it to sun. This pitch isn't combustable just for us to
have fun. It is combustable to produce fire. This is the very reason of
existance of it. For a long time now, human is the main ignitor of fire. So,
maybe plants adjusted to this. Maybe they were more combustable in the past,
who knows.
So, you are saying that pyrophyts aren't producing fire, and you are
saying that the big fire after first shower in savanna isn't started by rain
drops. Hm, this is what you are saying. I saw one documentray which deals
especially with that big fire in savanna, and specialsts for this claim that
it is started that way.
But ok, if you think you shouldn't waste any more time on this, it
is alright with me. I will waste more time. -- Mario


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