Deteriorating section of the UCIL plant near Bhopal, India. (Credit: Luca Frediani, Wikimedia)

Cleaning Up Bhopal: The World’s Worst Industrial Disaster

January 7, 2025 by Maya Posch 44 Comments

Forty years ago, on the night of Sunday 2 December of 1984, people in the city of Bhopal and surrounding communities were settling in for what seemed like yet another regular night. The worst thing in their near future appeared to be having to go back to school and work the next day. Tragically, many of them would never wake up again, and for many thousands more their lives would forever be changed in the worst ways possible.

During that night, clouds of highly toxic methyl isocyanate (MIC) gas rolled through the streets and into houses, venting from the Bhopal pesticide plant until the leak petered out by 2 AM. Those who still could wake up did so coughing, with tearing eyes and stumbled into the streets to escape the gas cloud without a clear idea of where to go. By sunrise thousands were dead and many more were left severely ill.

Yet the worst was still to come, as the number of casualties kept rising, legal battles and the dodging of responsibility intensified, and the chemical contamination kept seeping into the ground at the crippled plant. Recently there finally seems to be progress in this clean-up with the removal of 337 tons of toxic waste for final disposal, but after four decades of misgivings and neglect, how close is Bhopal really to finally closing the chapter on this horrific disaster?

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The Twisted History Of Ethernet On Twisted Pair Wiring

December 30, 2024 by Adam Fabio 55 Comments

We all take Ethernet and its ubiquitous RJ-45 connector for granted these days. But Ethernet didn’t start with twisted pair cable. [Mark] and [Ben] at The Serial Port YouTube channel are taking a deep dive into the twisted history of Ethernet on twisted pair wiring. The earliest forms of Ethernet used RG-8 style coaxial cable. It’s a thick, stiff cable requiring special vampire taps and lots of expensive equipment to operate.

The industry added BNC connectors and RG-58 coax for “cheapernet” or 10Base2. This reduced cost, but still had some issues. Anyone who worked in an office wired with 10Base2 can attest to the network drops whenever a cable was kicked out or a terminator was dropped.

The spark came when [Tim Rock] of AT&T realized that the telephone cables already installed in offices around the world could be used for network traffic. [Tim] and a team of engineers from five different companies pitched their idea to the IEEE 802.3 committee on Feb 14, 1984.

The idea wasn’t popular though — Companies like 3COM, and Digital Equipment Corporation had issues with the network topology and the wiring itself. It took ten years of work and a Herculean effort by IEEE committee chairwoman [Pat Thaler] to create the standard the world eventually came to know as 10Base-T. These days we’re running 10 Gigabit Ethernet over those same connectors.

For those who don’t know, this video is part of a much larger series about Ethernet, covering both history and practical applications. We also covered the 40th anniversary of Ethernet in 2020.

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Do You Know Vail Code?

December 27, 2024 by Al Williams 27 Comments

We talk about Morse code, named after its inventor, Samuel Morse. However, maybe we should call it Vail code after Alfred Vail, who may be its real inventor. Haven’t heard of him? You aren’t alone. Yet he was behind the first telegraph key and improved other parts of the fledgling telegraph system.

The story starts in 1837 when Vail visited his old school, New York University, and attended one of Morse’s early telegraph experiments. His family owned Speedwell Ironworks, and he was an experienced machinist. Sensing an opportunity, he arranged with Morse to take a 25% interest in the technology, and in return, Vail would produce the necessary devices at the Ironworks. Vail split his interest with his brother George.

By 1838, a two-mile cable carried a signal from the Speedwell Ironworks. Morse and Vail demonstrated the system to President Van Buren and members of Congress. In 1844, Congress awarded Morse $30,000 to build a line from Washington to Baltimore. That was the same year Morse sent the famous message “What Hath God Wrought?” Who received and responded to that message? Alfred Vail.

The Original Telegraph

Telegraphs were first proposed in the late 1700s, using 26 wires, one for each letter of the alphabet. Later improvements by Wheatstone and Cooke reduced the number of wires to five, but that still wasn’t very practical.

Samuel Morse, an artist by trade, was convinced he could reduce the number of wires to one. By 1832, he had a crude prototype using a homemade battery and a relatively weak Sturgeon electromagnet.

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Tech In Plain Sight: Incandescent Bulbs

December 26, 2024 by Al Williams 71 Comments

While they are dying out, you can still find incandescent bulbs. While these were once totally common, they’ve been largely replaced by LEDs and other lighting technology. However, you still see a number of them in special applications or older gear. If you are above a certain age, you might be surprised that youngsters may have never seen a standard incandescent lightbulb. Even so, the new bulbs are compatible with the old ones, so — mechanically, at least — the bulbs don’t look different on the outside.

You might have learned in school that Thomas Edison invented the light bulb, but the truth is much stranger (public domain)

It has been known for a long time that passing a current through a wire creates a glow. The problem is, the wire — the filament — would burn up quickly. The answer would be a combination of the right filament material and using an evacuated bulb to prevent the filament degrading. But it took over a century to get a commercially successful lightbulb.

We were all taught in school that Thomas Edison invented the light bulb, but the truth is much more complicated. You can go back to 1761 when Ebenezer Kinnersley first caused a wire to glow. Of course, wires would quickly burn up in the air. By the early 19th century, limelight was fairly common in theaters. Limelight — also known as the Drummond light — heated a piece of calcium oxide using a gas torch — not electric, but technically incandescence. Ships at sea and forts in the U.S. Civil War used limelights to illuminate targets and, supposedly, to blind enemy troops at night. Check out the video below to see what a limelight looks like.

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Why Did Early CD-ROM Drives Rely On Awkward Plastic Caddies?

December 18, 2024 by Lewin Day 46 Comments

These days, very few of us use optical media on the regular. If we do, it’s generally with a slot-loading console or car stereo, or an old-school tray-loader in a desktop or laptop. This has been the dominant way of using consumer optical media for some time.

Step back to the early CD-ROM era, though, and things were a little kookier. Back in the late 1980s and early 1990s, drives hit the market that required the use of a bulky plastic caddy to load discs. The question is—why did we apparently need caddies then, and why don’t we use them any longer?

Caddyshack

*Early CD players, like this top-loading Sony D-50, didn’t use caddies. Credit: Binarysequence, CC BY-SA 4.0*

The Compact Disc, as developed by Phillips and Sony, was first released in 1982. It quickly became a popular format for music, offering far higher fidelity than existing analog formats like vinyl and cassettes. The CD-ROM followed in 1985, offering hundreds of megabytes of storage in an era when most hard drives barely broke 30 MB. The discs used lasers to read patterns of pits and lands from a reflective aluminum surface, encased in tough polycarbonate plastic. Crucially, the discs featured robust error correction techniques so that small scratches, dust, or blemishes wouldn’t stop a disc from working.

Notably, the first audio CD player—the Sony CDP-101—was a simple tray-loading machine. Phillips’ first effort, the CD100, was a top-loader. Neither used a caddy. Nor did the first CD-ROM drives—the Phillips CM100 was not dissimilar from the CD100, and tray loaders were readily available too, like the Amdek Laserdrive-1. Continue reading “Why Did Early CD-ROM Drives Rely On Awkward Plastic Caddies?” →

It’s Critical: Don’t Pile Up Your Fissionable Material

December 12, 2024 by Lewin Day 52 Comments

Nuclear fission is a powerful phenomenon. When the conditions are right, atomic nuclei split, releasing neutrons that then split other nuclei in an ongoing chain reaction that releases enormous amounts of energy. This is how nuclear weapons work. In a more stable and controlled fashion, it’s how our nuclear reactors work too.

However, these chain reactions can also happen accidentally—with terrifying results. Though rare, criticality incidents – events where an accidental self-sustaining nuclear chain reaction occurs – serve as sobering reminders of the immense and unwieldy forces we attempt to harness when playing with nuclear materials.

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Retrotechtacular: 1980s Restoration Of San Francisco’s Cable Car System

December 11, 2024 by Maya Posch 43 Comments

The cable car system of San Francisco is the last manually operated cable car system in the world, with three of the original twenty-three lines still operating today. With these systems being installed between 1873 and 1890, they were due major maintenance and upgrades by the time the 1980s and with it their 100th year of operation rolled around. This rebuilding and upgrading process was recorded in a documentary by a local SF television station, which makes for some fascinating viewing.

San Francisco cable car making its way through traffic. Early 20th century.

While the cars themselves were fairly straight-forward to restore, and the original grips that’d latch onto the cable didn’t need any changes. But there were upgrades to the lubrication used (originally pine tar), and the powerhouse (the ‘barn’) was completely gutted and rebuilt.

As opposed to a funicular system where the cars are permanently attached to the cable, a cable car system features a constantly moving cable that the cars can grip onto at will, with most of the wear and tear on the grip dies. Despite researchers at San Francisco State University (SFSU) investigating alternatives, the original metal grip dies were left in place, despite their 4-day replacement schedule.

Ultimately, the rails and related guides were all ripped out and replaced with new ones, with the rails thermite-welded in place, and the cars largely rebuilt from scratch. Although new technologies were used where available, the goal was to keep the look as close as possible to what it looked at the dawn of the 20th century. While more expensive than demolishing and scrapping the original buildings and rolling stock, this helped to keep the look that has made it a historical symbol when the upgraded system rolled back into action on June 21, 1984.

Decades later, this rebuilt cable car system is still running as smoothly as ever, thanks to these efforts. Although SF’s cable car system is reportedly mostly used by tourists, the technology has seen somewhat of a resurgence. Amidst a number of funicular systems, a true new cable car system can be found in the form of e.g. the MiniMetro system which fills the automated people mover niche.

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