The Log Cabin syrup can, Dad’s gift of a morning science lesson
If memory serves me, I was about five or six years old, having breakfast in the kitchen at Gramma and Grampa Tompkins’ house in Portland, Oregon. But the old folks weren’t there, probably off at work or shopping on a Saturday morning. So it was just me, Mom, Dad, and my little brother Tommy in a highchair. It would have been about 1952 or ’53. Mom made pancakes, and it was a happy time of simple pleasures at the table, even though Mom mentioned her preference for margarine with its low cost while Dad insisted on real butter for its superior taste. But there was no disagreement about the Log Cabin maple syrup, which came in a cabin-shaped tin can with a little screw-on cap for a chimney.
After breakfast, Mom was washing the dishes, when Dad looked up from his Oregonian newspaper and said, “Tim-Boy.” (That’s what he used to call me.) “How would you like to help me in a little experiment?” Of course I nodded, Yes. Invitations from him, out of the blue, always led to interesting discoveries made through the Socratic method. He said, “Hold up your hand and blow on it.” So I blew a good puff at my palm. He asked, “How did it feel?”
A moment’s hesitation ensued as I wondered if he was looking for something prosaic or laced with special insight. “I don’t know, just like it always does, I guess.”
He pressed on, “What did your hand feel?”
“My hand felt the wind of my breath.”
“So what is this wind that you blew?”
“Just air. From my lungs. Going kind of fast. I pushed and gave it some pressure.”
“Good, we’re getting somewhere. Now this air that you breathe, we all breathe … does it have weight?”
“Well, an empty balloon falls faster than a full balloon, so air doesn’t seem to have weight, it seems to help things float. The opposite of weight.”
“Now that is an astute observation and a kink in the logical path I have in mind. You have a good head on your shoulders, Old Shoe. Let me ask another question. Do you remember the windstorm in The Wizard Of Oz that blew Dorothy’s house round and round and up into the sky?”
“Oh yes, the doors and windows were slamming. Something came loose and hit her in the head and she went into a dream.”
“That’s the way I remember it too, from when we saw the movie a few months ago. The question is, this air stuff must be rather substantial to lift a house or push a sailboat, no? Not just invisible fluff?”
“Not just fluff.”
“Suppose I told you that the air we are talking about is really an ocean of gasses all around us and above us, and we go through life walking on that ocean’s floor?”
I had nothing to say as I attempted to process this new concept, imagining the resistance and weight that I felt when moving my arms and legs in a swimming pool, or that Mom was feeling right now as she finished washing the frying pan in the sink, and shaking the syrup can with hot suds to clean out the residual stickiness, preparing the colorful tin log cabin for its new life as a kid’s toy. Dad’s theory of us living in an air ocean seemed like a stretch, but…
He went on, “And suppose you were to answer with something like, ‘Well, OK, if you say so,’ and I were to go a step further and try to assure you that it is true. Would you ask for some proof?”
Knowing that he did not want a yes-man for a son, not a yes-man to him or even to the Bible, I had to answer, “I would ask for some proof.” He and Mom had taken me off the enrollment sheet of the Baptist Sunday School a few weeks prior, since I had come home innocently singing, “Jesus loves me, this I know, ‘cause the Bible tells me so,” with its catchy tune and seemingly non-threatening lyrics. Dad hated any “just-close-your-eyes-and-believe” training in religion for the same reason he hated totalitarian regimes, be they fascist or communist. Having failed as a young preacher in a little country Calvinist church, he was a Libertarian by this time in the true sense of the word, even though he would vote Republican for several more decades, until the party swerved sharply away from its literally Conservative principles into debauched pragmatism for votes, as he would say.
But he kept things lively with the next question, “What if there were no air?”
More thought puzzles. I could do this. “Well, I think the clouds would fall down, and you couldn’t fly a kite or an airplane … and actually no one would be alive to try flying anything, even birds; but fish and whales in the ocean might be OK; and plants might be OK, but I don’t really know if they breathe air or not. Rocks wouldn’t care.”
He laughed, “Good! I won’t quibble with any of your fine points right now. We can always revisit them another time.”
A moment later he turned to Mom, “Charlotte, may I have that Log Cabin syrup can that you cleaned out so nicely?”
“Yes,” she said simply, handing it to him with the cap, as a trained nurse might have –which she was – watching what he was going to do with it.
“So Timmy,” Dad went on, “that experiment I mentioned a little while ago? Shall we do it now?”
“Sure!” I was perked up.
“OK. First, notice how this tin can is not shaped like a Campbell’s soup can, which is round like a little barrel. This one has flat sides, bottom, and ends. Much better for what we are going to see. Now what do we want to prove?”
“Something about us living in a big air ocean?”
“Right. An air ocean that is very deep, like 300 miles, getting thinner and thinner as it goes up toward outer space. So that, even though air is thin and wispy compared to water, it bears down with a serious amount of force because of how deep it is. We want to see that force in action. Are you with me?”
“Yes, I am with you, and so is Mom,” I laughed. “And so is Tommy,” who was observing intently, very much part of the moment. I leaned toward him and whispered, “Now be sure and remember this.”
Dad went on, “Let’s remove the air from this tin can and see what happens.” He moved to the electric stove and turned on one of the elements to a medium-low heat level, then asked me to fill the can with only about half an inch of hot water from the sink faucet, which Mom helped me do. Then he took the can and put it, uncapped, onto the stove.
Mom piped up, warning, “Jim, you aren’t going to build up steam pressure and risk bursting it here in the kitchen, are you? Have you thought about how hot the paint can get before filling the kitchen with smoke? And what about the solder that may be holding the seams of the can together? Are you sure you know what you’re doing?”
Dad laughed in the patronizing way he sometimes did to women, including his sisters and his wife, even us kids and our cousins sometimes. Mom didn’t like it, but she was into their marriage for the long haul, and she chose her battles carefully.
Dad explained, “We aren’t going to build up steam pressure, and we aren’t going to heat the can any more than necessary to make some steam. So, no worries. Let’s just watch and see what happens.”
Which we did. A minute went by. Another minute. Sometime in the third minute we began to hear the faint hissing of tiny bubbles forming in the can. But it took another couple of minutes to get a nice column of steam rising out of the cabin’s chimney. At that point, Dad put on an oven mitt, moved the can from the stove to the counter, and screwed the cap on tightly.
“Now, Old Pal, as we watch carefully, what do you think is going on inside the can?”
“Well, above the water, it is full of steam in there. But just sitting on the counter, it is going to cool down.”
“Yes, and what happens to steam when it cools?”
“It changes back into water?”
“Right again, my friend. What form of water?” I was stumped. He went on, “Remember when we talked about our famous Oregon rain a while back? About why it is wet on the ocean side of the mountains but dry on the other side?”
“You mean it’s going to start raining inside the can?!”
“You might put it that way. Steam has to condense into water on something, like the windows that you wrote on when learning how to spell at, bat, cat, fat, hat … remember those steamy windows? Or steam can condense into water on tiny dust particles way up in the sky and fall as rain. In this case, can you imagine what the steam might condense on inside the can, near the top, where it is cooling fastest … farthest from the water at the bottom, where it is cooling slower?”
“The roof?”
“It makes sense to me…” but he was cut short by the sound and sight of a significant crinkle suddenly forming in the side of the can facing us; it was clearly dented inward.
“Wow, what is going on in there that looks like sucking?” I asked.
“Well, sucking is one way to put it. But another way to put it is pressure from the outside taking over, nearly fifteen pounds for every square inch of surface it touches – about 100 pounds on just the palm of your hand, twice your body weight. Could you hold up 100 boxes of butter stacked on your open hand, even if you had perfect balance? Are you that strong? I would be hard-pressed to do it. The pressure dropping on the inside of the can is no match for that. Keep watching.”
“But why doesn’t my hand feel crushed?”
“Because you came into this world, even before being born, with that same pressure all around you and inside you. It’s not like your skin is being squished between a force from the outside and a force from the inside. Every tiny speck of your skin, every cell, all the way through, is pushing outward from its center to achieve a balance. If this weren’t true, you wouldn’t be alive. So here’s another thought experiment … what would happen if you were to suddenly jump into a vacuum, with no outside pressure?”
“I guess the air in my lungs would want to burst out?”
“Yes. The gasses in your guts too. Hmm, I don’t know about your fluids, like blood and the vitreous fluid in your eyes. I’ll have to think about that.” He fell silent. All four of us gazed at the poor Log Cabin can as it was slowly crushed all out of shape over the next few minutes.
Mom broke the silence when it seemed that the demonstration had run its course. “But I still don’t really understand why the pressure is dropping inside the can.”
With full respect for her good question, which was my silent question too, and without a trace of a patronizing attitude, Dad explained, “After you washed it, the can contained air inside and out. If there had been a pressure difference, air would have rushed in or out to balance that difference, since the cap was not screwed on. Then the water boiled into steam so thick inside the can that it pushed out nearly all of the air. The cap was still not screwed on, so the pressure inside still equaled the pressure outside.
“I removed the heat source when I moved the can to the counter and immediately screwed on the cap, so there was no more easy equalizing of pressures inside and out. Inner was isolated from outer. The steam condensed into water droplets and rejoined the water in the bottom of the can, leaving nothing but the diminishing quantity of remaining steam to fill the otherwise empty space. The cooler it got, the more moisture condensed, raising the water line and decreasing the pressure in the can. It would never reach a complete vacuum, because water molecules would always jump from the surface of the water. But the vacuum was sufficient to demonstrate the weight of air pressure on the can and on every part of us, including in our lungs, eyeballs, and brains.
Dad wrapped up with, “QED, quod erat demonstrandum: ‘Which was to be demonstrated.’ How do you like them apples?”
– By Tim Tompkins, 2021July04, what would have been Dad’s 102nd birthday, had he not died 23 years ago to the day, a real Forth-of-July guy.
(Epilog: I see that you can buy antique Log Cabin syrup cans for up to $275 on ebay these days. Would Dad have delighted in the can destruction recounted in this story if he had known? I think so; he was that committed to experimental evidence and teaching how to love the quest for verifiable knowledge, not the false faith and satisfaction of knowing that you have achieved it with finality. He was finally off the hook, a life achieved, as the light dimmed on his last breath, his last peaceful heartbeat, with Mom by his side.)