Why is There a Pyramid Atop the Washington Monument?

iStock / jkbowers
iStock / jkbowers

When the monument was constructed in the 1880s, aluminum was pretty rare and pretty expensive. Although it's very abundant in the Earth’s crust, the metal occurs tightly bonded and combined with other minerals, so it was very difficult and costly to extract. In 1884, aluminum was $1 per ounce, or about the same price as silver, and equal to the wage a laborer working on the monument got for one of his 10+ hour workdays.

Modern myth says that the pricey topper was sort of an "only the best" tribute to the first President, but the metal's value had no real impact on the decision, nor did the choice seem to involve any design evaluation, testing, or comparative competition among available materials. Instead, aluminum was selected because William Frishmuth, conveniently one of the only U.S. aluminum producers at that time, thought it could take a shock.

The pyramid was supposed to serve as a lightning rod, and since Frishmuth had already done some plating work for the monument, the U.S. Army Corps of Engineers called on him to fashion the topper as well. They requested a small metal pyramid, preferably made from copper, bronze, or platinum-plated brass. Frishmuth suggested that he instead use aluminum for its conductivity, color, and the fact that it wouldn't stain. He gave them a quote of $75, and the Corps agreed.

Frishmuth cast a cap that he called a “perfect pyramide of pure aluminum," weighing in at 100 ounces and standing nine inches tall. It was the largest piece of cast aluminum that had ever been created at the time, and Frishmuth was so tickled with his accomplishment that he arranged with the Corps to exhibit the pyramid in New York before he brought it to Washington. For two days, the pyramid sat in the window of Tiffany's in New York City, displayed like a precious jewel. Later, it was put on public display, on the floor, and visitors were allowed to carefully step over so they could tell their friends that they had walked "clear over the top of the Washington Monument."

Frishmuth's delays in delivering the pyramid to the monument site finally wore thin, and its tour came to an end when Colonel Thomas Lincoln Casey, the engineer in charge of the monument project, threatened him with force. The pyramid finally arrived with Frishmuth's request that it be displayed in the House and the Senate. He also wanted it wiped free of fingerprints with a chamois after being set atop the monument.

Budget Problem

Casey's eroded patience with Frishmuth completely gave way when he received the bill. Frishmuth exceeded his estimate by more than three times and submitted an invoice for $256.10. No more than a few hours after the papers arrived, Casey sent his assistant to Frishmuth's foundry in Philadelphia to investigate the bill. The entire accounting of the bill isn't clear, but one major factor in the unexpected cost appears to have been that Frishmuth could not use a standard sand mold to cast the pyramid and had to construct an iron one for the project. Another problem was that the cost of the aluminum alone, at the day's prices, was higher than Frishmuth's estimate of materials plus labor.

Davis managed to negotiate Frishmuth down to a final price of $225 and the pyramid was placed on top of the monument on December 6, 1884. But just a few months later, the pyramid fell down on the job. In June 1885, lightning struck the monument and cracked the north face of the spire just under the capstone. The pyramid was apparently not cut out to handle lightning on its own, and it was soon surrounded by a crown of gold-plated copper bars.

During a 1934 rehab of the monument's exterior, workers found another flaw in Frishmuth's pyramid. Repeated lightning strikes had blunted its tip, and pieces had melted and re-fused to the sides. Frishmuth's promise that the pyramid would not tarnish was good, though, and the inscriptions made on the metal 50 years prior were still readable.

7 Top-Rated Portable Air Conditioners You Can Buy Right Now

Black + Decker/Amazon
Black + Decker/Amazon

The warmest months of the year are just around the corner (in the Northern Hemisphere, anyway), and things are about to get hot. To make indoor life feel a little more bearable, we’ve rounded up a list of some of the top-rated portable air conditioners you can buy online right now.

1. SereneLife 3-in-1 Portable Air Conditioner; $290

SereneLife air conditioner on Amazon.
SereneLife/Amazon

This device—currently the best-selling portable air conditioner on Amazon—is multifunctional, cooling the air while also working as a dehumidifier. Reviewers on Amazon praised this model for how easy it is to set up, but cautioned that it's not meant for large spaces. According to the manufacturer, it's designed to cool down rooms up to 225 square feet, and the most positive reviews came from people using it in their bedroom.

Buy it: Amazon

2. Black + Decker 14,000 BTU Portable Air Conditioner and Heater; $417

Black + Decker portable air conditioner
Black+Decker/Amazon

Black + Decker estimates that this combination portable air conditioner and heater can accommodate rooms up to 350 square feet, and it even comes with a convenient timer so you never have to worry about forgetting to turn it off before you leave the house. The setup is easy—the attached exhaust hose fits into most standard windows, and everything you need for installation is included. This model sits around four stars on Amazon, and it was also picked by Wirecutter as one of the best values on the market.

Buy it: Amazon

3. Mikikin Portable Air Conditioner Fan; $45

Desk air conditioner on Amazon
Mikikin/Amazon

This miniature portable conditioner, which is Amazon's top-selling new portable air conditioner release, is perfect to put on a desk or end table as you work or watch TV during those sweltering dog days. It's currently at a four-star rating on Amazon, and reviewers recommend filling the water tank with a combination of cool water and ice cubes for the best experience.

Buy it: Amazon

4. Juscool Portable Air Conditioner Fan; $56

Juscool portable air conditioner.
Juscool/Amazon

This tiny air conditioner fan, which touts a 4.6-star rating, is unique because it plugs in with a USB cable, so you can hook it up to a laptop or a wall outlet converter to try out any of its three fan speeds. This won't chill a living room, but it does fit on a nightstand or desk to help cool you down in stuffy rooms or makeshift home offices that weren't designed with summer in mind.

Buy it: Amazon

5. SHINCO 8000 BTU Portable Air Conditioner; $320

Shinco portable air conditioner
SHINCO/Amazon

This four-star-rated portable air conditioner is meant for rooms of up to 200 square feet, so think of it for a home office or bedroom. It has two fan speeds, and the included air filter can be rinsed out quickly underneath a faucet. There's also a remote control that lets you adjust the temperature from across the room. This is another one where you'll need a window nearby, but the installation kit and instructions are all included so you won't have to sweat too much over setting it up.

Buy it: Amazon

6. Honeywell MN Series Portable Air Conditioner and Dehumidifier; $400

Honeywell air conditioner on Walmart.
Honeywell/Walmart

Like the other units on this list, Honeywell's portable air conditioner also acts as a dehumidifier or a standard fan when you just want some air to circulate. You can cool a 350-square-foot room with this four-star model, and there are four wheels at the bottom that make moving it from place to place even easier. This one is available on Amazon, too, but Walmart has the lowest price right now.

Buy it: Walmart

7. LG 14,000 BTU Portable Air Conditioner; $699

LG Portable Air Conditioner.
LG/Home Depot

This one won't come cheap, but it packs the acclaim to back it up. It topped Wirecutter's list of best portable air conditioners and currently has a 4.5-star rating on Home Depot's website, with many of the reviews praising how quiet it is while it's running. It's one of the only models you'll find compatible with Alexa and Google Assistant, and it can cool rooms up to 500 square feet. There's also the built-in timer, so you can program it to go on and off whenever you want.

Buy it: Home Depot

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14 Powerful Facts About the Hoover Dam

Ryan Thorpe, Unsplash // Public Domain
Ryan Thorpe, Unsplash // Public Domain

The hulking Hoover Dam has been holding back the Colorado River and generating power since 1936, but you may be surprised to learn just how eventful its construction and naming were.

1. The construction of the Hoover Dam forced Las Vegas to clean up its act.

Once the public caught wind of the plans to build a dam in Nevada’s Black Canyon, surrounding cities appreciated the potential economic windfall such an undertaking would bring. Las Vegas became especially eager to house the project’s headquarters, even going so far as to sacrifice its “party city” reputation to appear worthy of the honor. When Secretary of the Interior Ray Lyman Wilbur, a major player in the project, came to town for a 1929 visit, local authorities in Las Vegas shut down a slew of its speakeasies and brothels for the day in an attempt to seem classier.

2. An entire city sprang up to support construction of the Hoover Dam.

Panorama of Boulder City, Nevada from Water Tank Hill
1932 panorama of Boulder City, Nevada, from Water Tank Hill.
U.S. National Archives and Records Administration, Wikimedia Commons // Public Domain

Sin City’s efforts were ultimately futile, and a planned community went up to house the 5000-person workforce. Miles of paved streets and railroad tracks connected the canyonside village to the project site and neighboring Las Vegas. The community, known as Boulder City, is still standing. However, delays in its development forced a good number of early workers to reside in the nearby Ragtown, which lived up to its name with extremely humble living conditions.

3. The Hoover Dam contains enough concrete to stretch across the United States.

The Bureau of Reclamation—the department subsidizing the project—supplied a whopping 3.25 million cubic yards of concrete for the dam itself, plus another 1.11 million cubic yards for the power plant and additional facilities. This quantity of concrete would be enough to build 3000 miles of road—a full-sized highway from one end of the United States to the other. Additionally, the dam required about 5 million barrels of cement, nearly equaling the total quantity of cement the Bureau used in its previous 27 years of existence.

4. The world’s largest refrigerator cooled all the concrete used for the Hoover Dam.

As you may guess, all this concrete posed some challenges. Without engineers’ intervention, it would have taken the massive blocks of poured concrete 125 years to cool, and this gradual drying would have left the pieces susceptible to breaking. To speed up the process, an engineering team designed a mammoth refrigeration machine. The supersized fridge dispensed upwards of 1000 tons of ice every day, speeding up the cooling and lopping decades off the project’s timeline.

5. The first summer of construction on the Hoover Dam had record-breaking heat.

The giant fridge had its work cut out for it. Work on the Hoover Dam kicked off in April 1931, not long before Nevada’s Clark County weathered some of its hottest temperatures on record. The month of June delivered an average daily high of 119°F, prompting a wave of heatstroke among workers.

6. The Hoover Dam’s laborers were terrific showmen.

Native Americans employed on the construction of Hoover Dam as high-scalers.
A group of Native Americans who worked on the Hoover Dam as high scalers, 1932.
National Archives and Records Administration, Wikimedia Commons // Public Domain

Despite the punishing temperatures, construction attracted curious and enthralled spectators from across the country. Even more entertaining than the technological feats of the project were the death-defying antics of the “high scalers,” who rappelled down the Black Canyon to remove loose rock from the gorge’s walls. While one might expect such a job to be handled with extreme caution, the high scalers became famous for their playful, albeit ill-conceived, stunts.

Spectators were particularly fond of the antics of daredevil Louis Fagan, nicknamed “The Human Pendulum” and “One-Rope Fagan.” When teams worked on outcroppings in the canyon walls, they would move from one area to another by locking their arms and legs around Fagan and having him swing them to their next spot.

7. One heroic high scaler saved his boss’s life during construction on the Hoover Dam.

Fagan was impressive, but Oliver Cowan trumped his fellow high scalers when he snatched his falling supervisor right out of the sky. When Bureau of Reclamation engineer Burl R. Rutledge lost his hold on a safety line at the top of the canyon, he would have plummeted to his demise had Cowan, who was working 25 feet blow, not grabbed his leg as he fell. Shortly after the episode, the city of Las Vegas lobbied for a Carnegie Medal in recognition of the local man’s bravery.

8. The Hoover Dam’s chief engineer badmouthed his workers to the local press.

Not everyone was as impressed with the workforce. The hazards of the construction site and poor conditions in Ragtown contributed to the labor force’s decision to strike in 1931. A committee formed to express the workers’ demands, to which the project’s chief engineer and superintendent, Francis Trenholm Crowe, was defiantly unsympathetic. In fact, Crowe contested each of the team’s qualms with the suggestion of eagerness to have the workforce replaced. Print interviews in local news publications quoted Crowe as calling his men “malcontents” who he “would be glad to get rid of.” The hard line gambit worked, and eventually the laborers returned to work.

9. Nobody really wanted to name the dam after Herbert Hoover.

In retrospect, it seems strange that one of the country’s most impressive feats is named after one of its least beloved presidents. In fact, Hoover is understood to have only earned the honor through a political publicity stunt. In 1930, Secretary of the Interior Wilbur traveled to the site to mark the dam project’s official opening. He took advantage of the pageantry to declare, “I have the honor and privilege of giving a name to this new structure. In Black Canyon, under the Boulder Canyon Project Act, it shall be called the Hoover Dam.”

In other words, Wilbur named the dam after his boss. As Hoover was already widely maligned for his part in kicking off the Great Depression, the name was hotly contested. Wilbur’s successor, Harold L. Ickes, was a particularly vocal critic, and in 1933 he switched the in-progress structure’s name to “Boulder Dam.”

10. Herbert Hoover wasn’t even invited to the dam’s dedication.

Interior Secretary Harold L. Ickes delivers his talk at the dedication of Hoover Dam
Interior Secretary Harold L. Ickes delivers his talk at the dedication of Hoover Dam.
Bureau of Reclamation, Wikimedia Commons // Public Domain

Ickes was hardly alone in his low opinion of Hoover. His own boss, Franklin D. Roosevelt, didn’t think much of Hoover’s presidential acumen, either. When FDR oversaw the dedication of the still nebulously named dam in 1935, he declined to invite his predecessor and even refused to give Hoover the expected nod in his ceremonial speech.

11. The Hoover Dam didn’t officially take its name until 1947.

The dam spent the 14 years following Ickes’s proclamation without an official name. Ultimately, on April 30, 1947, President Harry S. Truman signed a law authorizing the original Hoover handle, recognizing the 31st president’s hand in bringing the dam to life in the first place.

12. Nazis attempted to blow up the Hoover Dam.

In 1939, the United States government learned of a pair of German Nazi agents’ scheme to bomb the Hoover Dam and its power facilities. Destruction of the dam itself was not the central goal, but hampering its energy production was a key piece of the agents’ plan to undercut California’s aviation manufacturing industry. To ward off aerial attacks, authorities considered camouflaging the Hoover Dam with a paint job or even building a decoy dam downstream from the real thing. Ultimately, the Germans only managed to get as far as conducting onsite investigative work before their ploy was quashed, thanks to an increase in military security around the dam.

13. Today, the Hoover Dam helps power three states.

The dam’s energy helps keep the lights on for customers in California, Arizona, and Nevada. It creates enough power for 1.3 million people.

14. The Hoover Dam was once the world’s tallest dam.

When it was finished in 1936, the Hoover Dam was remarkable not only for having completed construction a full two years ahead of schedule, but also for its unprecedented stature. The Black Canyon structure stretched 726 feet from base to top, practically soaring above the old record holder, Oregon’s 420-foot-tall Owyhee Dam. After holding the height title for two decades, Hoover was at last outdone by Switzerland’s 820-foot-tall Mauvoisin Dam in 1957. Eleven years later, it lost its domestic title to California’s 770-foot-tall Oroville Dam.