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The primitive hi-tech fire starters

I’ve never been much of a camping enthusiast. It’s not that I don’t appreciate all the great gadgets associated with camping, and I certainly enjoy hiking, fresh air, and getting away from it all. But after toting all our high-tech apparatus into the middle of nowhere, setting up a tent, and rolling out the sleeping bags, I invariably think to myself: this is an awful lot of work for very little comfort. At home I would have had a nice squishy mattress, a flush toilet, clean water, and no mosquitoes. Why am I doing this again? Then it comes time to build a fire and I discover some cruel corollary of Murphy’s Law at work. On those rare days I ever have to attempt this task, it’s always windy, damp, or both. Of course, I know that when matches fail, I can always bring out some specially flammable substance designed expressly for the pyrotechnically challenged. But the latest rage in fire-starting equipment is actually centuries old and uses no chemicals, sparks, or even metal components. Meet the fire piston: a deceptively simple tool that uses compressed air to start a blaze in just seconds.

Light Me Up

A fire piston is a small cylindrical object usually made of wood, bone, or plastic. It consists of two main parts: an outer casing, which is hollow but closed on one end, and the piston itself—a rod or plunger that fits the hole in the casing perfectly and whose tip reaches almost, but not quite, to the stoppered end of the tube. The tip of the piston has a small indentation or hole, and just behind the tip is usually a gasket of some kind to ensure an airtight seal—perhaps a rubber O-ring or simply some waxed string. In other words, very basic parts that require little technological sophistication to create.

To use a fire piston, you put a tiny piece of tinder in the indentation at the tip of the piston, and perhaps apply a dab of grease to the gasket for lubrication. Then you place the plunger into the tube and smack it down rapidly. This compresses the air inside, which raises its temperature. Within less than a second, the temperature at the tip of the piston can reach more than 800°F (about 425°C)—enough to turn the tinder into a glowing ember. The pressure also, conveniently, works as a spring that forces the piston back out of the casing. Transfer the ember to a larger pile of tinder, blow for a few seconds, and poof! You’ve got fire.

Pressure Cooker

In an earlier version of this article, I made the rookie mistake of believing something I read on some random webpage, and then compounded the problem by repeating that claim. The claim was that fire pistons work according to a principle called Charles’s law, but that is not only wrong, it’s pretty much the opposite of right. (Charles’s law has to do with the relationship between a gas’s pressure and its temperature, as in rising temperatures make the gas expand.) I hereby repent of my faulty reporting.

In fact, what’s going on is an adiabatic heating process, in which the rapid compression of the air increases its temperature as the pressure increases, and the system doesn’t leave that heat anywhere else to go. You can approximate this effect by inflating a tire with a manual tire pump—yet another piston design—and notice that the pump gets hot as you use it (although that type of design does provide an outlet for most of the heat). This very principle is what makes diesel engines work: the fuel is ignited by rapidly compressed air, not by a spark as in conventional internal-combustion engines. In fact, some people believe Rudolf Diesel may have gotten the idea for his engine from seeing a fire piston being demonstrated.

No one knows who invented the first fire piston. Although the device was patented in England in the early 1800s, a similar design (albeit made from different materials) was apparently in use long before that in Indonesia, the Philippines, and several other southeast Asian nations. The prevailing theory is that in the process of hollowing out a long tube to make a blowgun, a hunter inadvertently ignited some sawdust.

In any case, just as fire pistons were beginning to catch on in Europe, matches hit the scene, and quickly took over as the most popular method of making a flame. And so fire pistons were all but forgotten—at least in the western world—for the better part of two centuries.

But under certain conditions, matches are still no match for a fire piston. Because fire pistons create a watertight seal, they’re virtually weatherproof. And because you’re working with a glowing ember rather than an open flame, wind can actually work in your favor. You do, of course, have to have dry material to burn, but that’s pretty much a given if you’re going to start a fire by any means.

I first heard about fire pistons in an email from one of the many readers who regularly supplement my list of interesting things to research. After browsing a few websites—and, especially, watching some videos of the devices in action—I was simply astonished. I couldn’t believe that something so simple, effective, and useful wasn’t part of every camper’s gear. It might have been, had matches not been invented at just the right (or wrong) time.

Note: This is an updated version of an article that originally appeared on Interesting Thing of the Day on April 3, 2005.

Image credit: Chocolateoak [CC BY-SA 3.0], via Wikimedia Commons

When I was young, my friends and their families would head out to the commercial beaches for their vacations. By “commercial beaches,” I mean the ones with oceanfront hotels, boardwalks, and a dizzying array of lights. My vacations, however, were quite different, as they were spent at Assateague, a 37-mile-long island off the coast of Maryland and Virginia. The island is owned by both states, and the state line divides it in two. Because it is a national seashore and wildlife refuge, buildings on this island are few and far between. Not a hotel, restaurant, or arcade can be found here. The beach offers a 360° view of the sea and sky, with nothing to mar the experience except for horseflies and kamikaze kites.

What do you mean there’s no boardwalk?

Assateague is a natural barrier island, so it is constantly battered by water and wind. Its topography changes often. Since 1866, it has “moved” a quarter of a mile inland. My vacations were spent on the Virginia side of Assateague, and as a child I remember wooden steps and walkways that would take you up and over the high sand dunes. After being away from Assateague for a few years and then coming back as an adult, I found the high dunes were gone, and smaller, less-protective dunes had taken their place. Water and sand are constantly moving on this island. Changes in landscape and scenery on Assateague are expected and accepted.

Most visitors to the Virginia side of the island stay on the nearby island of Chincoteague. Because there are no hotels on Assateague itself, vacationers must drive onto the island and then out to the beach, a short 5–10 minute car ride from Chincoteague. Due to this relative isolation, you might find yourself wondering what appeal this island could have. Not for entertainment junkies, Assateague has many things to offer those who love an unspoiled beach. A short walk up or down the coast will take you away from the summer crowds and into remoteness, where you may only encounter a lone fisherman or wandering beachcombers. On the southern end of the island, 4-wheel drive vehicles are allowed (by special permit) to drive out on the sand, allowing access to the southern tip of the island and more secluded areas.

Aside from swimming, sunbathing, and fishing, the island has many outdoor activities. Nature tours are diverse and can range from marsh walks to bird-watching expeditions. Canoe and boat rentals allow for more personal and scenic views of the island and its waterways. There are also a myriad of chartered excursions for inland and ocean fishing. For those who don’t have their sea legs, crabbing and clamming are popular and easy. The Assateague Lighthouse, reached by a short walk through a pine forest, is occasionally open for visitors to ascend. Additionally, there are many bike paths that transverse the marshes and forests, allowing for close views of the vast populations of waterfowl, migratory birds, and mammals. At any other beach, an encounter with wildlife usually involves a seagull stealing your sandwich. At Assateague, wildlife and nature take center stage, and humans are merely visitors just passing through.

Pony Penning

Although a harsh environment, Assateague has a herd of wild ponies, more casually referred to as the “Chincoteague Ponies.” These horses have inhabited the island for at least 300 years. Originally thought to have swum ashore from a wrecked Spanish galleon, it is more widely believed that settlers brought them on the island to graze. Today they survive on marsh grass and other island roughage. Two separate herds exist, one belonging to each state, and they are kept isolated from one another by a fence at the border. Although true horses, they are often referred to as ponies due to their small stature, which is most likely a consequence of their marsh diet.

To keep the population numbers of the Virginia herd down, the ponies are annually driven across the channel in late July to the neighboring town of Chincoteague. Here, the horses (mostly foals) are auctioned off and the money collected benefits the Chincoteague Volunteer Fire Company. In recent years, individual horses were sold for an average of about US$2,300, with the largest bid being $25,000 in 2015 for a single horse! The last few Pony Penning events have auctioned off an average of 58 horses per year. The number of horses auctioned is dictated by herd size, as the Virginia side of Assateague Island is only permitted a maximum of 150 horses. After the auction, the remaining horses swim back across the channel and resume their lives on the island. The actual pony swim officially dates to the 1920s, although some form of pony herding has occurred since the 1700s. Pony Penning is an extremely popular event, and festivities span an entire week. Large crowds of hopeful bidders as well as spectators crowd onto the island. Today, Chincoteague ponies can be found all across the United States as a result of this auction.

Marguerite Henry wrote a notable series of children’s books about the horses and the annual swim. The first and most popular book, called Misty of Chincoteague, was written around 1948 and was based on a real Chincoteague family and their pony. This pony (the “real Misty”) died in 1972, and was allegedly stuffed and put on display. I don’t recall ever seeing the stuffed version of Misty while vacationing in Chincoteague, and I prefer to keep it that way.

Today the ponies can be seen in a variety of places on the island at different points of the day. They usually roam in smaller herds, and it is common to see them off in the distance relaxing under a copse of trees or grazing in the marshy fields. Closer encounters occur frequently along the wildlife trails and beach road; here tourists with cameras will crowd around, snapping photos as the horses languidly amble about. Signs posted all over state that “Wild Ponies Bite and Kick,” but that doesn’t seem to stop anyone from sidling up to them. They are part of the landscape and culture of Assateague as well as Chincoteague, and they make this already fascinating area even more extraordinary.

Editor’s note: In late 2018, it was reported that a serious infection has killed a number of the ponies, and authorities were working hard to both treat affected ponies and develop a vaccine.

The way it should be

As an adult, I still love to visit Assateague Island. Even though the nightlife is limited, and there are no boardwalks or flashy rides, a vacation here is what it should be: relaxing. There is no sense of hurry, no rush, no multilane highway packed full of cars ready to crowd the shore. It’s a shame to see how commercialized many beaches are becoming. But I guess we each have our own ideas as to how a vacation should be spent. Give me a view of the ocean in one direction, a dune full of sea grass in the other, and the possibility of ponies stomping up the shore. I want to enjoy the sun without a great big hotel looming over my shoulder. I can only hope that Assateague will always stay the way it is.

Guest author Jillian Hardee is an assistant professor in the Department of Psychiatry and a lecturer in the Department of Psychology at the University of Michigan.

Note: This is an updated version of an article that originally appeared on Interesting Thing of the Day on August 16, 2006.

Image credit: Bonnie U. Gruenberg [CC BY-SA 3.0], via Wikimedia Commons

Laundry without the hot air

During the years my wife and I were living in apartments—in San Francisco, Vancouver, and Paris—we always looked for units that had their own washer and dryer. We had both spent enough time using laundromats and shared communal laundry rooms to recognize that there is a positive correlation between convenience of laundry facilities and marital bliss. Even though such apartments were often harder to find and more expensive, we knew the extra effort was worth it.

Once when we were looking for a place, we came across an otherwise suitable apartment that included a small extra room with hookups for a washing machine, but no space for a dryer—nor any way to vent one. That sounded to me like a problem that ought to have a technological solution, so I began searching the web. Sure enough, I found a class of machines that used a single chamber for both washing and drying—put clothes in dirty, push a button, wait an hour or two, and take them out clean and dry. That by itself was interesting, but what really got my attention was the fact that these devices could dry clothes without any sort of vent. I had always assumed that hot, moist, linty air has to come out of a clothes dryer one way or another—it seemed like one of those cosmic truths you just couldn’t get around. But you can get around it, and surprisingly enough, one way to do so is to use water to dry your clothes.

Small Change

I first saw one of these machines when I went over to a friend’s apartment in San Francisco and saw one of the combo washer/dryer machines in the corner humming merrily along. After it washed his clothes, a different light came on and it started drying them. It didn’t give off any heat, which was actually slightly disappointing because that room was a bit chilly. He said it worked extremely well, the only minor drawback being that it had a relatively small capacity. According to the sticker on top of the machine, it was expected to consume about US$12 worth of electricity in a year—or about as much as a typical San Franciscan spends on coin-operated washers and dryers in a month.

But it wasn’t the compactness or energy efficiency of this machine that intrigued me, it was the way it got the clothes dry. Ordinary dryers suck in cool, dry air from the room, heat it, blow it through the clothes, and then discharge the damp, hot air outside through a vent. This dryer, on the other hand, runs the exhaust through a heat-exchange system to cool it. Cold water flows through the heat exchanger, absorbing heat from the air. As the air cools, the moisture in it condenses and runs down the drain (along with the used cooling water); the dry air is then heated again, sent back through the clothes, and the cycle continues. The upshot of this is that drying your clothes with a ventless dryer requires a few extra gallons of water, but eliminates the need for a vent and keeps your laundry room from overheating.

Years later, we moved into an apartment in Paris that had space in the kitchen for a washer, but nowhere to put a dryer. No problem—combination washers and ventless dryers were commonplace there, so we bought one and installed it in all of two minutes—we pretty much just plugged it in, attached the input and output hoses, and slid it into place. It served us well until we moved again, and we really dug the convenience of washing and drying all at once.

Air Apparent

Not all ventless dryers (or condenser dryers, as they are often called) have built-in washing machines, and not all of them use water to condense the moisture from the air. Another design—frequently seen in Europe but hard to find in North America—has heat exchangers that use cool air from the room to absorb the heat. This means that hot (but dry) air is discharged into the room; the condensed water drains away just as it does in the combination units.

It’s easy to find ventless dryers, washer/dryer combos, and even units that can switch between vented and ventless modes. Major brands available in North America include Equator, Haier, LG, and even Whirlpool. And yet, although these devices do solve a problem for those in places with limited space or venting options, they haven’t achieved widespread popularity, for a combination of three reasons: higher price, lower capacity, and longer drying time compared to conventional dryers. I hope that changes some day because—and I speak from experience—the whole notion that you can wash and dry your clothes with the push of a single button while keeping your apartment cool and dry fills me with geeky delight.

But there’s one final frontier of laundry automation, and it’s already on its way to a solution: folding. A machine called FoldiMate, projected to ship in late 2019 for about US$1,000, can fold shirts, blouses, pants, towels, and pillowcases as fast as you can feed them in. That’s extremely cool (if pricey for what it does), and the manufacturer hints that in the future they may incorporate wrinkle removal and other laundry care features. (It can’t fold underwear or pair socks, but I expect such capabilities aren’t too many years in the future.)

If the FoldiMate or something like it could be integrated with a washer/dryer, though, that would be just about perfect. I remember an old Lost in Space episode in which Mrs. Robinson put the family’s dirty clothes into a tabletop box, pressed a button, and then pulled out clean, dry, folded, and plastic-wrapped garments a few seconds later. That’s ultimately what I want. Then my wife will be happy to do the laundry while I replicate dinner.

Note: This is an updated version of an article that originally appeared on Interesting Thing of the Day on November 20, 2003, and again in a slightly revised form on September 11, 2004.

Image credit: Matthew Paul Argall [Public domain], via Wikimedia Commons