Mysteries of the Earth

Terra Preta as Terra Firma

For being one of the most verdant and lush places in the world, the Amazon rainforest has some of the worst soil on the planet. It's highly infertile. In fact, sand from the Sahara desert, blowing across the Atlantic Ocean, supplies many of the nutrients it needs.

When sand becomes a source of nutrition, I’d call that a mystery.

There are large patches of dark earth—known as terra preta—scattered all over the Amazon Basin that are inexplicably fertile. In fact, terra preta contains some of the richest soils on the planet.

For years, settlers were not sure where it came from. One common idea was that terra preta was the result of volcanic ashfalls originating in the Andes mountains. Eventually, though, we figured out where that soil came from: it was man-made.

The native peoples of the region had spent centuries managing the soil carefully. To make it fertile, they added a mixture of charcoal, bone, and manure to the soil.

You've heard of slash-and-burn, right? Well, the natives used slash-and-char, which involves turning the cut down plants and trees into charcoal (hence the name) instead of just burning it. The charcoal is then mixed with the bone and manure, and then buried within the soil.

The creation of terra preta isn't just an interesting type of fertilization, either. That soil stays immensely fertile for thousands of years. Charcoal is the most important ingredient: it lowers soil acidity, can absorb and then slowly release nutrients over time, and provides habitat to important soil microbes with its porous surface.

The other ingredients are important as well…though much of this remains a mystery. Scientists still do not fully understand terra preta. They are working quite persistently at it, though. I’d say that mastering the creation of terra preta would be a vital tool in regenerating damaged soils around the world.



Yes, the Quote-Off with that other Yard Ramp Guy. En garde:

“There are dark shadows on the earth, but its lights are stronger in the contrast.”

— Charles Dickens

A New Old-School Castle

Or: Undraining the Moat

gueldonThere's a castle under construction in France. Not a Disney-style castle at a theme park. An actual castle using medieval designs, materials, and construction methods.

Guédelon Castle started construction in 1997 and won't be completed until sometime in the 2020s. The designers aim to create an authentic 13th century-style medieval castle.

Oh, and when they say authentic, they mean authentic:

  • They only use local materials.
  • The site for the castle was chosen very carefully, located near an old stone quarry, a pond, and right in the middle of a forest.
  • All of the materials are gathered and hauled to the site using only medieval methods, including horse drawn carts.
  • The construction workers all wear period-appropriate garb, use period-appropriate tools, and use period-appropriate construction methods.
  • They have on-site blacksmiths, stone masons, carpenters, etc.
  • No modern tools are used anywhere. Not even ramps; sorry, Yard Ramp Guy.

The project has created 55 jobs and attracted more than 200 volunteers. On-site professional training is provided to disadvantaged youth, some of whom have earned stone-masonry and other certifications. More than 300,000 tourists a year visit the project, and it is open to schools for educational purposes. The construction has definitely proven itself worthwhile in those regards, but none of those were the original intention.

This is all part of experimental archaeology, which reconstructs and uses ancient tools, structures, and artifacts and allows archaeologists to actually study which methods work best and produce results most like the actual artifacts.

One way they do that is by looking for construction quirks (not the actual scientific term they use). Anyone who uses a lot of tools knows that you'll end up with certain quirks in your project, depending on which tools you use. For example: the same cut will be slightly different with different saws. When you're using tools that aren't mass-produced like ours, those little quirks get magnified even more.

During experimental archaeology, you can look to see if the methods you are using produce quirks like the historical ones.

Experimental archaeologists have produced Iron Age farmsteads and Greek triremes, hauled Stonehenge sized stones, sailed from Peru to Polynesia on a raft (Kon-Tiki), and, of course, built Guédelon Castle. (For a longer list, check out THIS. It's an incredibly productive line of research. And a heck of a lot of fun.

Guédelon Castle is proving to be one of the most productive of these lines of research. We've learned tremendously about castle construction from it. There was actually a companion castle being built in America: the Ozark Medieval Fortress. It ran out of funding and is currently on hiatus. We still need that European vacation to see a castle under construction. With any luck, though, that will change.


Photo By Ronny Siegel (Château Guedelon) [CC BY 2.0], via Wikimedia Commons

Go Jump in a Lake

Or: Good Luck Getting There

The most interesting lake in the world is completely inaccessible.

Well, maybe not completely, but close enough for government work. Which, come to think of it, usually isn't that close.

Lake Vostok is located in Antarctica. Bit of a strange place for a lake, I know, but this gets even weirder. Its surface is 500 feet below sea level. Lake Vostok is believed to have species of bacteria that are present nowhere else on the planet. It's also the largest lake in Antarctica, at more than 160 miles long and 30 miles wide.

lvAnd just to make all this interesting, there's a magnetic anomaly in one end of the lake.

Vostok Station, the nearby research facility, recorded the coldest known temperature ever on our planet. The lake has a single island, which no one has ever set foot on. It's also in complete darkness, even during the part of the year when Antarctica gets sunlight. That, of course, is because it's buried under 13,000 feet of ice.

As in: Lake Vostok is buried under a two and a half mile-high glacier.

Clearly impossible, right? Normally, yes, but in this case, the massive weight and compression created by the glacier caused its lowest layer to heat up, melting the ice and forming Lake Vostok. There are more than 500 of these subglacial lakes in Antarctic.

The hunt for life in Lake Vostok has become a major point of interest. Any creepy-crawly thing there would likely have been sealed off for the lake’s entire 15 million-year lifespan. The warm, oxygen rich, and pitch black waters would have created an ecosystem unlike anything else on the planet.

lv1Unfortunately, there are concerns that the antifreeze used to maintain the boreholes through the glacier might contaminate the lake, so scientists are proceeding with extreme caution. While the overwhelming majority of species they have found could quite likely just be contaminants from the surface, they have found at least one previously unknown species that might very well have come from the lake itself.

Mission to Mars? Sure. But Vacation in Vostok: now we’re talking…even though Maggie won’t hear of it.

Hutton’s Geology

James Hutton

James Hutton

Everyone knows about Charles Darwin and Galileo Galilei. They're the closest thing to science rock stars. One battled the Catholic Church at the height of its power and performed experiments involving dropping objects off buildings. The other took a voyage around the world and developed a whole new science. They have fascinating, memorable, and dramatic life stories. They’ve earned rock star status.

Geology has its own Darwin, but he's hardly as well known.

James Hutton was far from an adventurous man. In fact, most of his discoveries came about from exploring the same small area close to where he lived.

Hutton was a Scottish gentleman farmer, commonly known as the Father of Modern Geology. By observing layers of dirt and stone, he was the first to consider that these layers might indicate great age.

Man of Rocks

Man of Rocks

In his day (the mid and late 1700s), most other geologists looked to various theories involving floods to explain the layers. Hutton, though, theorized that the Earth was incredibly hot inside, and that sediment swept into the ocean melted and was pushed upwards. Which wasn't too far from today’s consensus, at least compared to most of his contemporaries.

Part of the reason that Hutton isn't well remembered today is that he was a much worse writer than other prominent geologists of the time. Hutton's book Theory of the Earth; or an Investigation of the Laws observable in the Composition, Dissolution, and Restoration of Land upon the Globe was much less readable for the general public. Plus, the title is just less catchy than, say, On the Origin of Species. Much, much less catchy.

Another reason? Rocks just aren't that interesting to most people.

The Lasting Architecture of Vastu Shastra

Indian architecture has one of the longest histories of any architectural school—or, at least, of any architectural philosophy. It's not like any society really ever stops building for a while, so they all have immensely long architectural histories.

Angkor WatIndia, however, has an architectural philosophy called Vastu Shastra. Rather than a rigid design philosophy telling you to do this and then do that, it's more a set of guidelines to help with maximizing space, sunlight, and movement within the space, while adding in Hindu and Buddhist beliefs. This all is characterized by square mandalas, which are very distinctive grid-like shapes.

Many of the greatest architectural achievements in human history were designed according to Vastu Shastra. Angkor Wat in Cambodia was designed according to that plan. (Fun fact: the live action version of “The Jungle Book” from the 1960s was partially filmed at Angkor Wat. Great movie.)

One theory holds that they developed Vastu Shastra as far back as 8,000 years ago; many ancient Indian archaeological sites conform to its design principals. It’s been in continual practice ever since, though it was ignored by a lot of architects during the British rule of India. As soon as the British got the boot, though, Vastu Shastra quickly started regaining its popularity.

Part of the reason Vastu Shastra has remained in use for so long is its flexibility. The design matrix allows for adaptation: with new building materials, in more crowded areas, and in non-square spaces. We’ve seen a major resurgence of Vastu Shastra in modern times—among both architects and homeowners in India—and its concepts are spreading all around the world.

Too often, people look at architecture, comment about how exotic it looks, and then just dismiss it as a novelty. People don't build like that, though. There is a philosophy behind every piece of architecture in history.