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Refrigeration Came Before Electricity
There's a book called Heartbeats of Colonia Diaz written by Annie Richardson Johnson, which tells about the Mormon colonies in Mexico, during the Pancho Villa days. The book is set in the late 1890's. It kept me glued to its pages as it talked of how the people won the hearts of the Mexicans by their ingenuity and hard work, and how they made a miniature paradise in that corner of Chihuahua, Mexico with their beautiful houses and buildings. They seemed to know secrets on how to grow fruits and vegetables that won prizes at fairs. My grandfather was there, and built a windmill that people, when they saw it, wanted one like it. He was also a lawyer there, protecting the properties of the colonists.
Of particular interest was the description of how they kept their butter cold: They put it out in the sun, of all places! They had a large bowl of butter that they put in a pan of water. Over the mound of butter they put a cloth that had good capillary action. The edges of the cloth hung down into the pan of water, and sucked up the water, providing a covering of wet cloth over the bowl of butter. As this set-up sat in the sun, the warm rays caused the water to evaporate. These days, we know that evaporation is a chemical reaction. We also know that a chemical reaction requires heat. Therefore, as the water evaporated, the chemical reaction sucked heat from the nearest substance: the butter, thus keeping it cool! As the cloth lost water to the evaporation, it was replenished when the cloth's capillary action brought in new water from the bowl beneath it.
Our swamp coolers that we put on our rooftops (in the sun) use this principle: Water dribbles down into the filter fibers, as the sun evaporates it. The chemical reaction sucks heat from the fibers, and when air is drawn in by the fan, the fibers cool the air as it passes through them. No refrigeration is achieved by anything electrical, at least directly: The electricity is used to provide the water, and suck in the air. The cooling is done by the physics of nature.
This made me wonder how people could know of such technical processes without the modern inventions. My curiosity brought me to the internet, where I learned that ice cream was made in the 1700's using the same principle: Salt, or salt crystals were added to ice, to lower the temperature for the freezing of the cream. Salt, when added to ice, causes an ion war, which, to make a long story short, lowers the freezing temperature of water. This is a chemical reaction, which draws heat from the cream, resulting in one of America's favorite desserts.
When I think of our ancestors, and the poor conditions in which they lived, I find I have been guilty of wondering about their mental capacities. But this discovery has given me more respect for their intellectuality. I've always had respect for their moral strength and their high character, but I forgot to think about their minds. I've concluded, now, that poor conditions do not necessarily produce poor mentality. I've even gone one step further: Too much technology, for us in these times, is probably turning our minds and creativity into mushy passiveness.