First off, I stacked and arranged the pile. This experience taught me much about combustion principles. First, to have sustained fire air has to get to it. Sawdust even though it is combustible can smother a fire by preventing air from reaching the burn. I learned this when I dumped a whole load on a fire already burning well. Once smothered it would continue to smoke but all flames would extinguish. If I poked it, brief flame would appear but quickly go out after I withdrew the poker. If I left the fire, by morning an intact pile of charred sawdust would still be smoldering.. But by then all chance of flame would be gone since heat had left. On the other hand if a handful of sawdust is thrown into the air above a roaring blaze it almost explodes in flame. Plenty of air among the dust particles makes for an volatile mixture.
Next, I learned that some things may not have been meant to be burned. Once in a while a small amount I put it the fire would release a cloud of noxious smoke. Mostly, it was thick black smoke that concerned me. Although she never complained a neighbor whose house was directly behind the shop would often be subjected to dense smelly vapors rolling across her property. I must have intuited that this was not good. Close by, I could tell by the stinging in my nose that what was being produced should not be shared, besides not likely being good for me.
I learned that with a hot fire small quantities could be rapidly burned without producing toxic clouds. But mostly, I gathered some elements were not meant for my fire and would be saved for hauling to a burial dump.
Lastly, I learned that some stuff doe not burn up even in a hot fire. Even small pieces of metal would not be consumed, ceramic and glass likewise. Sometimes these items would melt and change shape but never be burned up. They also glowed when subjected to high heat for a spell. I felt fortunate to be able to conduct fire experiments as part of my tasks. I took to making hot spots in the fire. In these places I conducted tests with most items that did not burn. I learned that such objects retained heat long after being removed from the furnace, often times hot enough to cause burns or ignite fires. I suppose these experiments taught me much about fire safety.
Not only was I lucky to have a chance to play with fire, I learned the joys of just watching a it burn and letting my mind drift to the accompaniment of the moving light show. We did not have a television back then, but I do not think I missed much. I learned that there is always a good show to be had just watching flames perform their magic.