Come, children, and sit as Grandpa Lampen continues his story of wire, which we began to tell in September and discussed most recently in the Jan. 15 issue.
There was a breakthrough in 1839 that, many years later, would dramatically affect the wire and cable business. That breakthrough was “vegetable leather.”
At least that’s what it was named by its inventor, Charles Goodyear. In 1834, he visited a rubber company in Boston. They were in the process of accepting back all the rubber products they had made during the previous years: boots, hats and raincoats. In hot weather, they had all turned to stinky goo, and the company was near bankruptcy.
For five years, Goodyear experimented with combining various powders and other compounds with rubber to make it stable at all temperatures. After hundreds of experiments, he added sulphur and heated the mixture by steam under pressure. This created stable, dry, non-melting rubber, eventually named vulcanized rubber.
All the while, he was in and out of prison for debt. Six of his 12 children died, and he and his family were starving and penniless most of the time. He died in 1860, still in debt, having invented vulcanized rubber. The company was named only in his honor, and was not owned or controlled by the family.
You can read the whole story at www.goodyear.com/corporate/strange.html, which reprints a 1950s Reader’s Digest article on this topic.
A killer slam dunk
The next thread of our story begins in 1520, when Hernan Cortez and his happy band of Spanish Conquistadors arrived in the Aztec capital, Tenochtitlan, known today as Mexico City.
The Aztec culture was at its height and must have been astonishing to the Spanish invaders. One of the things that amazed them was a game called tlachtli. It was much like basketball. A ball was put through stone hoops, 8 to 10 feet high, located at the ends of a court. You can still visit these courts throughout Mexico and Central America, built by the Aztec, Maya and Olmec cultures.
There were a couple of minor differences between tlachtli and basketball. First, the players couldn’t use their hands. So making even a single “basket” was incredibly difficult and won the game.
Second, the losers were beheaded. I’m sure this last difference made these games especially exciting, as the Conquistadors were into blood in a big way. But in their excitement, they really didn’t notice one unusual thing: the ball.
It was about the size of a modern soccer ball and weighed around five pounds; some weighed as much as 15 pounds. But the unusual thing was that it bounced. It was made of cured rubber.
In 1496, Columbus brought back a rubber ball on one of his trips, and whole teams of players later were transported to amuse Charles V, King of Spain. These rubber balls maintained their shape and did not melt into a pile of goo during hot weather, which is pretty much the normal weather in Central America.
Fast-forward to 1996, to a classroom at MIT in Cambridge, Mass. A student named Michael Tarkanian was taking an elective class on living anthropology from Associate Professor Dorothy Hosler. The professor was talking about the Aztec civilization, including the game, tlachtli, that used a rubber ball. Tarkanian, a chemical engineering major, interrupted to say that a rubber ball in 1500 was impossible because the “vulcanizing” process wasn’t invented until 1839 by Charles Goodyear.
The Mayans, Aztecs or Olmecs didn’t know what sulphur was, nor did they have pressurized steam vessels to cure the rubber. Therefore, said Tarkanian, it was impossible for anyone in 1500 to have cured “vulcanized” rubber.
Hosler challenged Tarkanian, and they settled the matter by having him change his major to materials science and engineering and leading a team to Central America to find out if, indeed, the ancient culture that lived there could make cured rubber.
They started by sampling ancient rubber balls recently excavated from a swamp in Veracruz, Mexico. Sure enough, they were cured rubber, latex mixed with sulphur. But how did they do it? And did that knowledge survive to this day? Now how would you go about finding this out? Tarkanian did this in an amazingly simple, but effective way.
He walked into the jungle and asked a native walking by if he knew how to make stable cured rubber. No problem, said the native, and proceeded to show the team how: take uncured rubber from a rubber tree (latex), add in the juice of the morning glory vine (which contains a lot of sulphur) and do it on a very hot day.
What comes out is indeed vulcanized rubber.
In fact, further excavations have revealed cured rubber objects as old as 1600 BC. It should be pointed out that both the rubber plant and the morning glory vine were considered sacred plants by these cultures, so mixing them together may have been a lucky mistake – in 1600 BC. Perhaps the fact that the morning glory is hallucinogenic was a contributing factor.
Tarkanian became of the few undergraduates to co-write a paper for Science magazine. You can read the “the story of rubber” at www.psrc.usm.edu/macrog/exp/rubber/aepisode/tlachtli.htm.
Rubber is used to insulate wire. Few plastics are as rugged. Despite the mixing and the curing, a hot and smelly process, rubber-insulated wire and rubber-jacketed cables continue to be made.
There is only one real problem with rubber: it comes from Central America. We cannot grow rubber trees here in the United States. As we will see, this became a major problem and, except for a bit of luck, could have been a major blow to us in World War I.
In the first column of this series I talked about how the “battery” was invented in 200 BC and later lost. Here, yet again, another invention was discovered and lost, if only for 339 years.
What if we had not lost this knowledge? For that matter, what knowledge is slipping through our fingers today? Sometimes inventions come from basic necessity, such as measuring the size of a wire.
How do you measure a wire? Where do you start? Tune in next time for another amazing story in the history of wire and cable.