Boiling points. I remember learning that different liquids had different boiling points. It was in junior high. It's one thing to learn it in your head, but to see someone stick their hand in a boiling pan of alcohol--you expect them to pull their hand out and for it to be painful and blistered and red Not so. Alcohol boils at a temperature not too much above body temperature....
But the most vivid demonstration that sticks in my memory is when Mr. Browning, in Chem I, took a gigantic glass flask (like a 10-gallon flask, with sides at least an inch thick) that was full of ice water and made it boil. Impossible you say? Nope. Even the temperature at which water boils is affected by the pressure over it. By creating a vacuum in the flask, Mr. Browning was able to make the ice-cold slush contained inside it BOIL! Boiling slush. Such an unusual sight, it's still in my memory like it was yesterday, and it was over 30 years ago!
We use the same principle in pressure cookers. Just as water boils at a lower temperature under less pressure (which is why you have to cook things longer at higher altitudes, by the way-less atmospheric pressure); it boils at a higher temperature under pressure. That is why we use a pressure cooker for canning starchy vegetable snd meats, so they will "boil" at a higher temperature, a temperature high enough to kill the dangerous bacteria, like botulism, which can withstand normal boiling temperatures.
But an interesting thing happens as a jar of water is boiled in a pressure canner. As the water boils inside the jar at hotter-than-normal boiling temperatures, air is forced out of the jar. As the jar then cools, the lid seals before it has reached room temperature, creating less pressure inside the jar than there is on the outside. That's why when you open the jar, you hear that characteristic "shoop" as air rushes in to equalize the pressure.
The interesting thing is this. because the water inside the jar is under less pressure, it will now "boil" at a lower temperature than water under normal atmospheric pressure.
I think that is why Joy bubbles up through all kinds of circumstances. It may look odd to us to see people joyfully worshiping God on the streets of Haiti, amid hunger and stench and unknown futures. But it's really the same thing as seeing a boy put his hand in a boiling kettle of alcohol or ice-cold slush boiling. They have been "cooked" under pressure, and their boiling points have been lowered. Joy bubbles up through it all.
I "listen" to my teenage friends on Facebook struggling under the pressures of their lives, and I remember being a teenager, and how hard it was; and yet, being an adult is so much harder. But we don't get there overnight--most of us. We are boiled in the pressure cooker of life over and over, hotter and hotter, under more pressure each time, until we get to the point where we bubble at room temperature.
Q and A with Bob Welch
1 week ago