Archives: Roman Concrete

Learning from the School of Hard Rocks

My good friend Jeff Mann, the true Yard Ramp Guy, has asked me to revisit some of my original posts. This week in my From the Archives series: Roman concrete.


It's Written in the Concrete

Though the Romans have a pretty impressive reputation, in many regards they weren't nearly so clever as people tend to think they were.

For example, their fabled legions, while effective early in Roman history, became rather useless toward the end: the knight was basically invented by barbarians looking to defeat Roman legions. Even after it became apparent that the legions were a tool of the past, the Romans foolishly just kept sticking with it.

However, one area in which they were unquestionably brilliant was in architecture and construction.

Much has been made of Roman aqueducts and other construction techniques, but one technology that doesn't get discussed nearly as much as it should is their concrete. Roman concrete—known as opus caementicium—is, interestingly, much more durable than modern day concrete.

We have many examples of Roman concrete that have survived all the way to today. The Pantheon in Rome (not to be confused with the Parthenon), for instance, is a concrete dome that has survived intact since 126 AD.

Even more impressive is Roman concrete's resistance to seawater. Seawater is incredibly corrosive to modern buildings, corroding and destroying them in mere decades. We're lucky to get 50 years out of modern concrete. Roman concrete, however, can survive immersion in seawater for centuries or even millennia; plenty of docks and pilings from Roman times can still be found off European shorelines.

What was their secret? Well, we don't know the exact composition of Roman concrete, but we do know one of the major secrets: they used volcanic ash instead of the fly ash we use today. When submerged in seawater, the seawater reacts with the mineral phillipsite, found in volcanic ash. Over time, a new mineral known as tobermorite forms in the cracks of the concrete. As it forms, the concrete actually gets stronger and stronger.

Roman concrete today is stronger than when it was first laid down.

Many people are trying to mimic Roman concrete today. Not only is it more durable and long lasting, but it's also cheaper and more environmentally friendly. The problem, of course, is the extremely long setting time: most builders don't want to wait long enough for Roman concrete to set.

Haste makes waste. Some people are okay with that. Roman concrete endures.

Yard Ramp Guy Blog: Manufacturing Outlook

This week, my friend The Yard Ramp Guy shows how his inventory contributes to the larger picture of the U.S. economy.

Click HERE to see how it all fits into place.

Archive: Your House is a Fossil Museum

Or: Kitty Litter Paleontology

My good friend Jeff Mann, the true Yard Ramp Guy, has asked me to revisit some of my original posts. This week in my From the Archives series: what's that archaeology team doing in my kitchen?


My watchdog never needs walking.

We usually think of fossils in the context of museums, but you might be surprised to hear that they're probably in your home without you knowing.

The first way this happens is pretty obvious: if you've got limestone as part of the construction of your house. Limestone is almost universally fossil-bearing. In fact, many types of limestone are almost entirely made up of fossils. So, if you have limestone in your house, you've probably got fossils.

Of course, fossils can be found in other rocks as well, such as certain sandstones and mudstones, though limestone is the most common fossil-bearing rock used in construction.

Next is in kitty litter. Bentonite clays are used in countless industrial settings, but they also have one extremely common use inside the home—as the main ingredient of most kitty litter products. Bentonite clay is highly absorbent, making it ideal for this purpose.

Another thing bentonite clay is famous for? Occurring near fossil formations. The Morrison Formation, the geological formation where Dinosaur National Monument is found, is also heavily mined for bentonite clay. There have also been plenty of reports of kitty litter mining companies in Canada knowingly destroying fossil beds for more profit. So... your cat might be doing its business in dinosaur bits.

Third is diatomaceous earth. This fine white powder is frequently used as a cleaning product in the home. Applications of it can kill many types of insect infestations. The actual mechanism by which it does so is a little complicated, but it essentially dehydrates the insects to death. (Sometimes it's also used in kitty litter.) Diatomaceous earth is a sedimentary rock composed entirely of fossilized diatoms, a type of ocean-going microorganism that grows a silica-based shell.

Finally, there's good old-fashioned chalk. Chalk is simply an accumulation of the shells of tiny marine microorganisms, just like diatomaceous earth. Instead of being formed of silica-shelled organisms, however, it's formed out of calcite-shelled organisms known as coccolithophores. (Interestingly, the Cretaceous is actually named after the fact that more chalk was deposited around the world than during any other geological era—not, as you might expect, due to anything to do with dinosaurs.)

So, whenever your kids are drawing on the sidewalk with chalk, they're drawing with fossils.

Yard Ramp Guy Blog: Save By Buying

This week, my friend The Yard Ramp Guy describes what's hiding in plain sight, and how we can save money from it.

Click HERE to uncover everything.

Archive: Roads as History

My good friend Jeff Mann, the true Yard Ramp Guy, has asked me to revisit some of my original posts. This week in my From the Archives series: roads are literally, yes, a roadmap of history.


McCoy Fields Roads

Paved with (Good?) Intentions

I write a lot about roads on this blog. The Yard Ramp Guy must think I'm a bit obsessed (though he’d probably phrase it differently).

The study of roads is the study of history. Countless historical events, from the outcomes of wars to international trade, and from religious expansion to the maintenance of nations: they all rely on roads.

Incan roads—not the most extensive network of ancient roads but one of the most technologically impressive—were earthquake-proof with incredibly durable suspension bridges. Roman roads have been receiving acclaim for millennia now, and many are still in use.

Which brings us to ancient Chinese roads.

Under the Qin Dynasty (circa 220 BC), Chinese road networks were considerably more extensive than their Roman contemporaries. One, the Ancient Road of Mules and Horses, was created in 214 BC by an advancing army of the Qin. The Emperor marched a half-million strong army in a straight line on one of his wars of conquest, crushing the earth in its path. They later covered the road in slate, and it remained in use for 2,000 years afterward without changing routes.

Walking up a golden ramp. Kind of.

Walking up a golden ramp. Kind of.

Road maintenance was key in holding onto territory in China. Later dynasties, like the Han, went to great pains to maintain this and other roads, building hostels and post offices along their lengths. Another Qin road was immensely long, built to service border forts along a huge wall that predated the Great Wall.

My favorite ancient road of all, though, is the Stone Cattle Road. One of the ancestors of the First Qin Emperor wanted to conquer the nearby Shu kingdom to the south, over the Qinling Mountains. He had his sculptors and artisans carve five life-sized stone cows and decorate their tails and hindquarters with gold.

When the king of Shu received news of them, he asked the Qin king to send him a herd. The Qin king claimed that he would need a gallery road (built of wooden planks imbedded in the sides of cliffs) across the mountains to move the cows. The Shu king not only permitted it; he also helped fund the construction.

Yes, we know how this story develops: The first thing the Qin king brought over wasn't a herd of gold-depositing cattle. He brought an army.

Yard Ramp Guy Blog: Business Advantages

This week my friend The Yard Ramp Guy shows how buying his inventory can save you money.

Click HERE for his simple suggestions to make that happen.

Archives: Of a Certain Age

My good friend Jeff Mann, the true Yard Ramp Guy, has asked me to revisit some of my original posts. This week in my From the Archives series: if it smelts fishy, it could be the remnants of the Stone Age. Or Bronze. Or Iron.


ape2-300x168We’ve heard of the Stone Age, the Bronze Age, and the Iron Age. And yet, we aren't commonly taught why those ages occurred in that order. Which is just too bad, since it's pretty darn interesting.

The Stone Age has a simple explanation. Stone is easier to work than metal, and more common. We figured out how to use it first.

Ancient humans actually did master use of some metal during this time period — namely meteoric iron, a natural alloy of nickel and iron present in iron meteorites. We sometimes heated it but more often shaped it, by cold hammering, into tools and arrowheads; the stuff was quite difficult to work.

The ancient Inuit inhabitants of Greenland, though, used iron much more extensively than other Stone Age people. Greenland has the world's only major deposit of telluric iron, also called native iron, which is iron that occurs in its pure metal state.

Looking for the right tool to advance our evolution

Native copper, however, is found worldwide (as are native gold, silver, and platinum, all of which are of limited use for tools.) The hardest and strongest common native metal on Earth, copper proved one of the most useful.

Eventually we learned to smelt metals from ore and, around 2500 BC, learned to alloy the two together to make bronze, kicking off The Bronze Age. Tin was somewhat rare outside the British Isles, parts of China, and South Africa, so it actually ended up commanding prices higher than gold in many regions. We frequently used zinc, more common than tin, to produce brass.

Iron smelting first occurred circa 1800 BC but didn't become common until 1200 BC. Eventually, of course, iron became the metal of choice for civilization—it's just much stronger than most of the other options.

Yard Ramp Guy Blog: Bracing for the Elements

This week, my friend The Yard Ramp Guy shows us how he's long been prepared for weather-related events.

Click HERE to discover a textbook-perfect example of being proactive.

Archives: Raising a City

My good friend Jeff Mann, the true Yard Ramp Guy, has asked me to revisit some of my original posts. This week in my From the Archives series: It turns out that buildings can be very moving experiences.


Stay with me on this one: yes, it begins on a pretty sour note…but I promise you there’s a happy ending.

Raise High the Roof Beams, Carpenters

Nineteenth century Chicago was plagued by, well, plagues. Epidemics of typhoid fever, dysentery, and cholera repeatedly hit the city. The 1854 cholera outbreak killed six percent of the entire city's population.

The reason for those diseases, and a common culprit throughout history: poor-to-nonexistent drainage. Standing water in a city makes a perfect breeding area for all sorts of nasty illness. In fact, disease historically was so bad that the majority of medieval cities experienced negative population growth—more people died of diseases than were born.

The only reason cities didn't depopulate was a near constant influx of immigration from the country. This changed steadily around the world when city infrastructure and medicine improved. Disease was still quite common in the 19th century, but Chicago's level of disease was quite unusual in an American city for the time.

In 1856, an engineer named Ellis S. Chesbrough developed a plan for a city-wide sewer system that would solve the problem. It was unusually ambitious: he wanted to raise the entire city six feet, then build sewers below the newly raised buildings.

Sounds insane, right? That's what I thought, too, except they actually did it—raising the first building in January 1858: a four-story, 70 foot long, 750-ton brick structure lifted on two hundred jackscrews to its new level, without the slightest damage. Engineers boosted more than 50 masonry buildings that year alone.

In 1860, a team of engineers actually managed to raise up half a city block in one go—an estimated 35,000 tons lifted nearly five feet into the air by 600 men using 6,000 jackscrews. They were so confident in the process that businesses didn't even close during the the five days it took to lift the whole thing.

On the last day of the process, before they began work on the new foundations, they allowed crowds to walk underneath the buildings, among the jacks. At another point, a six-story hotel was raised up without the guests even realizing it.

Only masonry buildings were considered worth raising; they placed wood-framed buildings on large rollers and moved them to the outskirts of town, usually without even bothering to empty out the furniture first.

This was so common that, for quite a few years, people considered looking out the window to see a building going past just another day of normal traffic.

The Yard Ramp Guy Blog: Angling Yard Ramp Strategy

This week, my friend The Yard Ramp Guy riffs on Yogi Berra's great quotation: "When you come to a fork in the road, take it."

Click HERE to see what direction The Yard Ramp Guy chose to take.