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Tag: history (Page 1 of 2)

Saran Wrap Isn’t What It Used To Be

In the 1960s, I used to help my mother in the kitchen and learned how to cook. I used Saran Wrap to cover plates and bowls, and I noticed that this material was sort of magical. It stuck to what I wanted it to stick to and wasn’t much inclined to stick to itself. What is this sorcery? You could pull it back to access something in a bowl, then seal it back up again. I was fascinated because it seemed like it was intelligent. I had studied some chemistry but not yet enough to guess the cause for this marvelous behavior.

So what was this wonderful material I was working with? In 1933 a chemist at Dow Chemical was trying to develop a new dry cleaning solvent. He noticed that certain beakers and glassware were hard to clean. They had a residue that was hard to scrub off. Investigation revealed a new substance, a new polymer that was named polyvinylidene chloride or PVDC.

It was found that, among other things, PVDC made a tough and durable clear coating. During World War 2, virtually every U.S. aircraft was coated with PVDC to help protect it from the elements. At the end of the war, hundreds of companies in the U.S. got busy looking for commercial applications for the countless marvelous things they had developed for the war effort. Somebody at Dow realized that PVDC would make an excellent food wrap. And excellent it was, as you will see later. Production methods for forming PVDC into a very-thin film were developed. The CEO of Dow decided to name it after his wife and daughter, Sarah and Ann: Saran.

The product was introduced in 1949 and was an almost overnight success. This is the stuff I was using in the 1960s. Towards the end of the 1960s, Dow’s patents expired and other companies began producing PVDC food wrap, like Glad Wrap. They were all just copies of Saran Wrap.

From the 1990s forward, I didn’t use much plastic food wrap until I began to work in a restaurant in 2012. There, I used plastic food wrap all the time and immediately noticed that it behaved differently from what I remembered. Sure, it worked, but it frequently refused to stick to some things and it was eager to stick to itself. This is not what I remembered. After opening and closing a covered bowl, the plastic wrap would become wrinkly and refused to stick to anything. I covered a mixing bowl full of diced onions with this plastic wrap and placed it in the cooler. Soon, the cooler smelled strongly of onions. What? That’s not supposed to happen. What is this stuff? Maybe some kind of cheap imitation of Saran Wrap?

Time passed, I finally did some digging on the Internet, and immediately found the answer. Through the 1990s, chlorinated polymers like PVDC became an increasing environmental concern. In 2004, all the makers of PVDC plastic wrap switched to ordinary low-density polyethylene (LDPE). Polyethylene is cheap and easy to make into a thin film. But there are problems. Big problems.

First of all, polyethylene is a low-friction, non-stick kind of polymer. This is why milk bottles are made from it. Polyethylene film doesn’t stick to anything, nor itself. Today’s polyethylene plastic food wrap is coated with a moisture-activated adhesive to make it “cling”. At best it clings to certain things but not others, and it eagerly sticks to itself, making it hard to work with.

Secondly, the adhesive quickly wears out so opening and reclosing a bowl covered with modern plastic wrap is something you might be able to do once but not repeatedly, like you can with PVDC film.

Thirdly, polyethylene film is around 3,000 to 4,000 times more permeable than PVDC film. Oxygen is the main culprit that causes food spoilage. For every one molecule of oxygen that a given area of PVDC film lets through, polyethylene film lets through 3,000. The consequences of this are obvious. This also explains the experience I had with onions stinking up the cooler. That wouldn’t have happened with PVDC film. In fact, certain meats are still packed with PVDC film because polyethylene film can’t do the job.

The bottom line for me is that I was pleased to discover that my memories from the 1960s were pretty accurate. However, I was not pleased to discover that the plastic film I use today is inferior in terms of performance and user friendliness, and there’s no way to fix it.

Today’s plastic wrap looks like classic Saran Wrap, but it ain’t. It’s not even close.

Trump Reaction Meme

Quote from Mueller's report

Quote from Mueller’s report. Click to view larger.

The above is a popular meme today. It’s a quote from Mueller’s report quoting Trump’s reaction to learning he was under investigation.

Loath as I am to defend Trump, I must point out there are two ways to interpret Trump’s comment. One is that he’s guilty of something and fears being found out. The other is an astute reaction to learning he’s under investigation.

In the past, presidents who are under investigation are hobbled and unable to get much done while the investigation is going on. The mere existence of an investigation hamstrings them, regardless of what the findings turn out to be. His reaction would be appropriate for any president, even one who’s completely innocent.

So, his reaction could mean, “Oh, crap, they’re onto me. I’ll get caught,” or it can mean “Crap, they just tied my hands and I can’t carry out my job as president until this is over.”

Which one is correct is an exercise for the reader. My guess is that it’s the former, for two reasons. 1.) Trump has a long history of shady / criminal behavior. 2.) He’s likely ignorant of the history of presidents who were under investigation.

Time may tell which is correct.

Coal Mining Isn’t What It Used To Be

When I was growing up in the 1950s and 60s, the term “coal miner” conjured up a stereotypical image of a man covered head to toe with black coal dust, wearing a hard hat, and swinging a pick or shovel. The work was grueling, dangerous, deadly, and paid terrible wages. In the United States, a shocking 90,000 men lost their lives in coal mines between 1900 and 1950. If there was ever a line of work that could be called “the widowmaker”, it was coal mining. The rest of society viewed coal miners as the bottom of the social hierarchy.

You load sixteen tons, and what do you get?
Another day older and deeper in debt.
Saint Peter don’t you call me ’cause I can’t go,
I owe my soul to the company store.

 –Tennessee Ernie Ford

Harry Fain, 1946 National Archives Photo

Today, coal mining is used as a political football by politicians. Politicians know that it conjures up powerful images that are based on the stereotype I described above. Most recently, President Trump invoked these images repeatedly during his campaign, and it created the desired effect on his listeners.

However, coal mining today isn’t what it was in 1910. The above stereotypes are completely false today. Coal mining has changed radically as have the men and women working in that business. President Trump’s rabble rousing was based on fantasy and imagery that no longer exists.

Back around 1910, there were thousands of coal mines. Larger mines employed hundreds in each shift. Virtually all coal mining was done underground, not on the surface. This meant entering or descending into deep mines. The standard mining technique was room and pillar, which dates back to ancient times. A room is hollowed out with pillars of coal left standing to support the roof. The size of the pillars was based on the opinions of experienced miners. Sometimes, they were wrong. There’s a tradeoff involved. Making the pillars larger provides increased safety but reduces the amount of coal that can be extracted.

Room and pillar is still used today in mines where there’s a valuable enough deposit, like anthracite (hard coal) and surface mining isn’t feasible. However, instead of relying on seat-of-the-pants guesses, science and engineering is involved. The force on the ceiling can be calculated, the compressive strength of the coal deposit can be measured. Optimal column sizes can then be calculated and actual stresses measured so danger can be detected and averted.

For added excitement and profit, one can still get the material left behind in the pillars by a method called retreat mining. Once a room is exhausted, the pillars can be destroyed, one by one, starting with the deepest one. The ceiling is allowed to collapse and the coal recovered. Needless to say, this is a dangerous business. My two coal miner friends here in West Virginia do this kind of work. With modern technology, it can be done successfully and accidents kept to almost zero.

My friends still come home from work with black faces and clothes full of black coal dust — hard shiny anthracite coal particles that sparkle when you look at them. They use the two washing machines at the laundromat set aside especially for coal miners. Unlike their counterparts a hundred years ago, they don’t use a pick and shovel, are highly skilled, and are paid well. But, they are in the minority. The majority of coal is produced nowadays using surface mining, including the infamous mountaintop removal mining technique. Fortunately for the environment, the number of mountaintop removal permits has dropped to about half of what it was ten years ago. This might be from political pressure, or because coal sales have dropped sharply since 2008. I don’t know. The economic collapse of 2008 started a sharp decline in coal sales that continues today. Demand has dropped. Again, President Trump’s rhetoric about increasing jobs in coal could only happen if demand increases. Coal mines are not gold mines, where the demand is essentially infinite. Coal mines produce only the amount of coal that is needed.

Surface mining, which produces the majority of coal today, is done by comparatively few highly skilled workers using gargantuan machines worth millions of dollars each. These machines are so large that you have to see them in person to comprehend. Imagine a bulldozer that could drive down one side of your neighborhood and obliterate every house on one side of the street in a single pass, without the least effort. Or, a dump truck so large that it’s not apparent where the driver is located. You have to climb three flights of stairs to reach the cab. Coal mines of this type employ more people who are mechanics, machinists, welders, engineers, and explosives experts than those who actually do the mining. It’s a whole different world from coal mining in 1910. What’s more, over the next ten years, more of these machines will become robotically controlled with no operator. In twenty years, surface mining will likely be done entirely by computer and robots.

Let’s look at some numbers. In 1900 the population of the country was 76 million and the coal industry employed 500,000 men. So, the better part of one percent of the population, or 1 out of every 152 men in the country, was a coal miner.

In 1900, annual coal production was about 275 million tons. From 1900 to the present, coal production increased to a peak of almost 1,200 million tons in 2008. In 2008, the US population was about 307 million, and the coal industry employed about 70,000 people, nationwide, or 0.02 percent of the population. In 2008 we had one seventh the number of people producing five times as much coal as we did in 1900. Coal production efficiency per worker is 35 times what it was in 1900.

To put these employee numbers into perspective, consider that Walmart employs 1.5 million people in the USA. Amazon employs 570,000. The US Postal Service employs 503,000. The coal industry employs 70,000. To increase production, the coal industry would add a few more machines and a few more employees to accommodate demand. So, to base a political campaign promise on increasing jobs in coal mining is disingenuous at best, stupid at worst. Coal is one of the worst sectors to choose to make such a promise. The number of jobs in coal mining will not increase significantly no matter what happens. The only reason to make such a promise is because it has strong emotional appeal to voters because they still have the old coal miner stereotype in their head and don’t know how things have changed.

Sixty Years in Southern California 1853-1913

If you were born and raised in Los Angeles and/or are interested in the history of the Southland (Southern California), there is a wonderful book for you.  “Sixty Years in Southern California 1853-1913” by Harris Newmark is a great book about the history of Los Angeles and the Southland from 1853 to 1913, written by a person who lived it.

When I was growing up in the 1950s and ’60s I was fascinated to learn the origin of some of the street names like Sepulveda, Pico, and Olvera. Sepulveda is named after the Sepulveda family, owners of tens of thousands of acres now occupied by Palos Verdes. Pico Blvd. is named after Don Pio Pico. When I was five years old, my uncle’s house was near Winslow Drive and Micheltorena, and I thought Micheltorena was such a strange word. I had not yet learned to speak Spanish, nor did I know that Micheltorena was a well known person in 19th century Los Angeles.

As time went on I learned more but I’d never before found a book like this one–jam packed with information. Written by a businessman who immigrated from Germany to Los Angeles in 1853, the author personally knew everyone of any importance in the Southland over a period of 60 years. He writes the story of LA as it grew from a few adobe buildings and dirt streets, complete with gold miners and gunslingers, to a modern metropolis.

Here’s a short list of names in the book that should sound familiar to any Angeleno: Juan Temple, owner of the 27,000 acre Los Cerritos Rancho, after whom is named Temple Street; Don Abel Stearns, owners of tens of thousands of acres between San Pedro and San Bernardino including Los Coyotes Rancho, La Habra Rancho, San Juan Cajon de Santa Ana Rancho, and the Los Alamitos Rancho upon which now sits the City of Long Beach; John G. Downey; Bernard Yorba, owner of the land upon which now stand the City of Anaheim, Orange, Santa Ana, Westminster, Garden Grove, and other parts of Orange County, which was then part of Los Angeles County; Willliam Workman and John Rowland, owners of the 49,000 acre La Puente Rancho; Don Luis Vignes, owner of the land now occupied by East LA; The Dominguez Family, owners of a 48,000 acre land grant from the King of Spain; Dr. del Amo; Henry Dalton, owners of the Azusa Ranch and Duarte; Manuel Garfias, owner of the 14,000 acre San Pasqual Ranch upon which were built Pasadena and South Pasadena; Don Ygnacio Machado, owner of La Ballona; Colonel Jonathan Trumbull Warner, owner of the Warner Ranch upon which part of Orange County now sits; Benjamin Davis Wilson, owner of most of San Gabriel, after whom Mt. Wilson is named; Colonel Julian Isaac Williams, owner of the Cucamonga and Chino ranches; Don Pio Pico, owner of a 22,000 acre rancho and after whom Pico Blvd. is named; William Wolfskill, owner of Rancho Santa Anita and Rancho San Francisquito upon which Newhall now stands; Don Jose Ygnacio Lugo, owner of the land upon which Santa Barbara now stands; Louis Robidoux, owner of the Jurupa Rancho upon which now sits the City of Riverside and after whom Mt. Robidoux is named; Juan Forster, owner of the Santa Margarita Rancho and Las Flores Rancho; and the Verdugo Family, owners of a 36,000 acre land grant from the King of Spain dating from 1784 and upon which now sits the City of Glendale.

Interested? The above really is a short list. The author knew all of these people personally and many more. The book contains vast amounts of first hand information.

“Sixty Years in Southern California 1853-1913” is available for free download from The Gutenberg Project:

http://www.gutenberg.org/ebooks/42680

The epub version includes all the photo plates from the book. I highly recommend it.

Or, get a real copy of this excellent book:

Sixty Years in Southern California by Harris Newmark

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