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My dad and I were driving in southern Texas one summer afternoon in the early 1960s when we came over a rise and drove down upon a blanket of tarantulas. Thousands upon thousands of black, hairy beasts the size of small pancakes blanketed the highway. When dad hit the brakes, the wheels skidded, being greased with spiders hell-bent on crossing the road. It made quite an impression.

Ten years later, my new bride laughed at my entomological horror tale, but her scorn dissipated entirely the following summer when she and I encountered a similar tarantula migration while driving in western Texas.

Tarantulas were common at our alma mater of North Texas, where we met. Their bite isn’t deadly or terribly painful, so a jolly collegiate prank was collecting tarantulas after rainstorms when they emerged from underground burrows and slipping them under dormitory doors of prankees. But we’d find a couple of tarantulas, not thousands.

Years later, I learned that massive uphill migrations were the weather-sensitive creatures’ response to incipient gully-washers.

Spiders bother many people, especially tarantulas, being the biggest and hairiest spiders on Earth. The largest tarantula of all, Theraphosa leblondi, aka “the Goliath bird-eater,” grows as big as twelve inches, can live 30 years, and possesses amazing hunting and defensive reflexes.

In the Natural History article, “The Importance of Being Hairy,” Samuel Marshall described digging up a leblondi’s burrow. She hissed at him and then “responded by brushing a rear leg rapidly downward across the rear of her abdomen, releasing a small cloud of shed hairs. Suddenly, my hands and throat were burning and itching furiously, a sensation that persisted for several days.”

Excellent photos of this shedding and the multi-barbed tarantula hairs are in a book by Sy Montgomery called “Tarantula Scientist.” Montgomery describes how tarantulas “periodically shed all the exoskeletal ‘skin’ — and even the lining of their mouth, stomach and lungs.” Golly! Dwell on that for a moment.

Montgomery notes how tarantulas “can regrow lost legs. Sometimes a tarantula will pull off its own injured leg — and then eat it.” Nothing about spiders, however, is more incredible than their silk.

Even the expression “spider” derives from its silk production. The word “spider” comes from the Old English term, “spithra,” from the ancient Danish word “spenwanan,” meaning “to spin.” I often turn to children’s publications like “Tarantula Scientist” when researching ambitious new topics, for the information is usually basic and clear.

My son, Gabe, and I were discussing orb weaver spiders we’ve seen in Alaska and wondered what spider hair and silk are made of. Since the library’s online databases can be searched from home, we soon learned from an article by Emily Sohn in “Science News for Kids” that spider silk is a booming business.

Spider silk is non-polluting, biodegradable and incredibly strong. Sohn writes, “researchers have found that spider silk can be as much as 100 times tougher than the same amount of steel, and far tougher than Kevlar.”

So why aren’t there spider farms producing this super thread? Unlike silkworms, individual spiders can’t produce big volumes of silk, don’t breed well in captivity, and are carnivorous.

Nexia Biotechnologies has successfully used spider genes to create silk-producing goats to make BioSteel, “recombinant dragline spider silk” for body armor and other applications. Don’t hold your breath for a spider silk suit, however, for Nexia recently decided to focus on “non-scale fibre applications for spider silk and away from traditional fibres and yarns.”

Producing this silk is incredibly complex, but a summary of how Nexia does it is at www.nexiabiotech.com/en/03_bio/05.php.

Transgenic goat silk and plain old spider silk are truly remarkable, but no more so than our national network of free public libraries that allow anyone to learn anything that stirs their curiosity. The American public library we know today, freely dispensing the best knowledge available on every subject while protecting its users’ privacy, is open to all races, religions, classes and ages. It is quite a fragile institution that’s existed only half a century.  It’s working together as a national system of information-sharing that makes libraries amazingly powerful information generators for the communities they serve. As an old Ethiopian proverb puts it, “When spider webs unite, they can tie up a lion.”

Greg Hill is director of Fairbanks North Star Borough libraries.