by Vince Beiser
It was the British, those indefatigable experimenters (and long-ago Roman subjects), who started bringing concrete back. In the 1750s, an English engineer named John Smeaton, while tinkering with various binding agents to hold together the granite blocks he was using to build a lighthouse off the coast of Plymouth, came up with an excellent formula for hydraulic (water-using) cement. (You can add other materials like gypsum, and play around with burning temperature and grain size, to change the properties of cement.11 Today, there are hundreds of formulas for making cement tailored to specific weather conditions, project types, and other variables.)
Others continued tweaking the mixture, which came to be called Roman cement. By the early 1800s, hydraulic cement was sufficiently trusted to be used in the construction of a tunnel for horse-drawn carriages under the Thames River.12 The tunnel was later adapted for trains, and reconstituted in 2010 as a museum.13
In 1824, a forty-four-year-old English bricklayer named Joseph Aspdin was granted a patent for his own cement formula. It was a mixture of powdered limestone and clay, fired at high temperatures, which he dubbed Portland cement, since its color was similar to the famous limestone from the Isle of Portland14 in southern England. Aspdin had been trying for some time; hard up for expensive materials, he was twice charged with stealing limestone from paved roads. His was just one of many patents given in those years to inventors of various cement formulas, but his took off. That was partly because it was stronger and more durable than the competition, and partly because Aspdin’s son William seriously exaggerated its quality in his marketing pitch.15 Nonetheless, it has become the industry standard; today, 95 percent of the roughly 83 million tons of cement manufactured in America is Portland cement.16
Various tinkerers were intrigued by the crude concrete you could make by mixing sand and gravel with Aspdin’s cement. In the early 1800s, an artist named James Pulham started making vases, sculptures, and architectural adornments out of concrete. Others tried it for architectural purposes. “Although largely ignored by most people during much of the nineteenth century, the idea of using concrete to cast walls and floors to make houses was an appealing challenge for a few brave souls active in the cement industry,” writes Courland. “Perhaps a dozen concrete houses were built in England in the 1850s, and a few still remain.”17
The problem with concrete is that it has tremendous compressive strength, which means it can stand up to great pressure without breaking, but it has little tensile strength, which means it can’t bend much without shattering. That limited its usefulness. By the mid-1800s, inventors and entrepreneurs were looking for ways to increase concrete’s tensile strength. The most promising approach was to embed it with iron, essentially giving it an inner skeleton that absorbs the stress from bending pressure, keeping the concrete from fatally cracking.18
A French farmer came up with the unlikely-seeming idea of using concrete reinforced with iron bars to build a boat. The thing did actually float—for a little while, anyway. Then it sprang a leak and promptly sank to the bottom of the farmer’s pond. In 1867, a gardener named Joseph or Jacques (accounts differ) Monier, another Frenchman, wanted stronger tubs for large plants than the standard fired-clay ones. He came up with a system of reinforcing concrete with loops of metal wire.19
This was a crucial breakthrough. On its own, concrete is basically artificial stone. Reinforced with iron or steel, though, it becomes a building material unlike anything found in nature, one that combines the strengths of both metal and stone. That’s what makes it so useful for so many purposes.20
Builders in Europe and the Americas dabbled with the new material.21 The first home built with reinforced concrete went up in Rye Brook, New York, in the early 1870s, the project of an engineer named William Ward. It’s still there. At the time, it was the world’s largest reinforced concrete structure.
It was right around this time that a young man named Ernest L. Ransome set out from his home in Ipswich, England, to seek his fortune in booming, bawdy San Francisco. Ransome was a scion of a family of ironworkers and engineers that had helped develop products from lawn mowers to ball bearings. Ransome’s father, Frederick, branched out into making and selling artificial stone, and developed his own cement mixture. Ernest started apprenticing in his father’s factory in 1859 at age seven. At that time, as he later wrote, “the concrete industry was in its infancy, and was confined largely to the manufacture of artificial stone for ornamental purposes.”22
Ransome, a trim and stern-faced fellow, arrived in San Francisco in the early 1870s. It was an excellent place and time for an ambitious, inventive type. Grown rich from the Gold Rush, the city was by then a hub for the new Silver Rush in nearby Nevada, and a base for moguls of the mining, manufacturing, and railroad industries. It was growing fast; the population quadrupled between 1860 and 1880 to nearly a quarter of a million.23 Ransome found a job at a company that produced concrete blocks for paving stones and architectural decorations,24 and talked his colleagues into switching over to his father’s brand of cement. Within a few years, he left to start up his own outfit. He sold concrete vases and cement components (he eventually abandoned his father’s brand for the standard Portland cement), and in his spare time noodled around trying to develop new reinforcing techniques that would make stronger, more durable, more versatile concrete.
In the early 1880s, San Francisco city authorities decided that the standard wooden sidewalks weren’t strong enough to cope with the growing numbers of pedestrians that were pounding up and down them every day. They began replacing the old walkways with sturdier ones made of concrete. This of course was great for the concrete makers’ business. The San Francisco Chronicle reported in 1885 that sales were surging as “artificial stone for sidewalks and basements is coming into general use in nearly all the larger towns on the coast.”25
One forward-thinking local contractor built some of these sidewalks using a technique, patented by an American inventor named Thaddeus Hyatt,26 of reinforcing the concrete with embedded iron bars. Impressed with the results, Ransome set about experimenting with variations on Hyatt’s method and soon came up with a historic innovation. He took two-inch-thick square iron bars, attached their ends to an adapted cement mixer he set up in his backyard, and twisted the bars, like a towel being wrung. The twisted bars gripped the concrete more firmly all along their length, and the process of twisting them also increased their tensile strength. It was the first version of the now-standard steel rebar used in reinforced concrete structures around the world.
Nonetheless, as Ransome recalled a few years later, convincing his peers wasn’t easy. “When I presented my new invention to the technical society of California, I was simply laughed down, the consensus of opinion being that I injured the iron,” he writes in his prosaically titled book, Reinforced Concrete Buildings. It took many tests before he began to win converts.27 Ransome patented the system in 1884, the same year he built the first large commercial structure made with reinforced concrete, a warehouse in San Francisco for the Arctic Oil Company. He followed that with the Alvord Lake Bridge, an arched pedestrian tunnel under the main thoroughfare running through Golden Gate Park, and two important buildings for the campus of the new Stanford University, south of the city in Palo Alto.
Reinforced concrete kept proving itself, and Ransome’s business grew rapidly. He became the nation’s foremost evangelist of concrete. He was awarded patents28 for a range of additional processes and machines, and began leasing out his system for use far and wide. One of the reasons for his success was that Ransome was a stickler when it came to sand. There are gradations of quality even among common construction sand, and Ransome would accept only the finest into his service. “Next to the cement, the sand is the most important factor in determining the strength of the concrete,” he told would-be builders in his book. “It is well understood by skilled concrete men that the best grade of sand is clean, sharp, and well graded from fine to coarse.�
��29
Meanwhile, the price of steel was plummeting, thanks to rapidly advancing production methods and the discovery of titanic deposits of iron, steel’s basic raw material, in Minnesota. Those lower prices made it feasible to replace iron rebar in concrete with steel, making the concrete even stronger. Cement was getting cheaper, too, giving concrete an economic edge over steel and masonry buildings. The upstart material made headlines around the world in 1901, when contractors using Ransome’s system put up Cincinnati’s sixteen-story Ingalls Building, by far the tallest concrete structure on the planet and one that nearly matched the height of the biggest skyscrapers then in existence.
Still, by 1906 there were very few reinforced concrete buildings in California. That was largely thanks to bitter opposition from powerful building trade unions, especially on Ransome’s home turf of San Francisco.30 Bricklayers, stonemasons, and others, correctly seeing in concrete a mortal threat to their professions, denounced it as unproven and unsafe. Just a few months before the quake, a group of bricklayers and steelworkers in Los Angeles tried to convince the city council to forbid the construction of any more concrete buildings31 within municipal limits.
The tradesmen also made a case against concrete on the grounds that it was plain ugly. An article in The Brickbuilder, a monthly trade publication, complained in May of 1906 that “a city of the dull grayness of concrete would defy all laws of beauty. . . . Concrete does not lend itself architecturally to anything that appeals to the eye. Let us pause a moment before we transform our city into such hideousness as has been suggested by concrete engineers and others interested in its introduction.”32
Concrete, however, kept gaining ground. In retrospect, the process to a certain extent resembled the rise of computers many decades later. At first, people could see that this new technology was promising, but who knew if it would actually work better than the tried and trusted old ways? Why risk your business on some newfangled invention when your trusty paper ledgers, or your dependable bricks, did the job just fine? For quite a few years it was only the early adopters—the inventors, the hackers, the hobbyists—who played around with the new thing in its early, crude forms, figuring out how it could be used. But gradually concrete, like the computer, became more refined, dependable, and easier to use, until it reached a point where practically anyone could work with it.
There was no single point at which concrete definitively eclipsed other building methods. But the fact of the survival of the Bekins warehouse, along with the many other concrete foundations, floors, and full-scale buildings that stood up well to the 1906 earthquake and subsequent fire, was a watershed. (The warehouse was in such good shape that the company turned it into a shelter for newly homeless locals.)33 The concrete industry certainly thought so, and wasn’t shy about using photos of the rubble to promote their cause. “The American cement industry has grown up through a mass of prejudice, the last vestige of which was overthrown and buried by the splendid showing made by concrete in the San Francisco earthquake and fire,” declared the June 1906 issue of Cement and Engineering News.34
Trade press editors weren’t the only ones convinced. Captain John Sewell of the Army Corps of Engineers, one of three authors of a 1907 report commissioned by the US Geological Survey on the San Francisco earthquake’s damage, declared that the “great utility of reinforced concrete in earthquake shocks can not be denied” and that a “solid monolithic concrete structure of any sort is secure against serious damage in any earthquake country,” unless “it should happen to lie across the line of the slip [seismic fault].” He also decried the “opposition of the bricklayers’ union and similar organizations” that had “prevented the use of reinforced concrete in San Francisco for all parts of buildings. This action of the labor unions will cost the city a good deal, and, should it be continued, will cost a great deal more in the future.”35
In Concrete Planet, Courland contends that Sewell and the other authors of the USGS report were “biased in favor of reinforced concrete construction and against masonry building,” noting that one of them later became president of the National Association of Cement Users. Indeed, several reinforced concrete buildings in San Francisco were seriously thrashed by the quake, while some brick buildings came through just fine—facts that were ignored or downplayed by the USGS investigators.36
It didn’t matter. Concrete won the public relations battle. An article in the San Francisco Chronicle a few weeks after the fire gushed that “these buildings and parts of buildings passed the ordeal of the earthquake practically uninjured . . . re-enforced concrete roofs and floors passed triumphantly through the earthquake.” The newspaper concluded: “We now have re-enforced concrete, in great measure perfected and proved for our use. With it we can . . . build comparatively light and even graceful and handsome structures that will have the bearing strength of natural stone, the tensile strength of steel to resist the disrupting influence of shocks, much of the artistic effect of carved stone, and a lasting and fire-resisting quality which will surpass them all.”37
San Francisco building codes, however, still forbade the use of concrete in high, load-bearing walls. Ransome and his fans wanted that provision changed, but traditional tradesmen saw it as their last line of defense. The urgent need to start rebuilding the city gave impetus to concrete’s case. Some 225,000 people were left homeless by the quake, more than half the city’s population. (A Los Angeles Times article on the dispute added that labor shortages were another issue slowing down construction. Things were so dire that one “William Maxwell of the Pacific Wrecking Company has been forced to employ Japanese, paying them white man’s wages.”)38
Two months after the quake, the San Francisco board of supervisors held a meeting to discuss whether to change the code. So many would-be speakers on both sides of the argument showed up that one of the supervisors complained that hearing them all “would take a year.” In the end, the anti-concrete faction lost. The board allowed concrete construction to go ahead.
The bricklayers didn’t give up, though. The following year the union banned its members from working on buildings using concrete, and threatened to boycott “every other branch of the building industry connected with them,” reported the San Francisco Chronicle.39 But by then the war was already lost. “There is scarcely a block in the down-town burned district but will not soon boast of at least one reinforced concrete building, for they are to be on every hand seen in various stages of construction,” reported a local newspaper in 1907.40 By 1910, the city had issued permits for 132 new reinforced concrete buildings. Moreover, nearly all new steel-frame buildings built after the fire included concrete floors. “There were still obstacles to building with reinforced concrete as late as 1911, but these only slowed down the use of concrete,” writes architectural historian Sara Wermiel. “The floodgates were open.”41
A few months after the earthquake, Thomas Edison—the Steve Jobs of his day, inventor of the lightbulb, the phonograph, and much else—gave an after-dinner speech to a crowd of New York dignitaries assembled in his honor. Someone asked him what his next miraculous invention would be. “Concrete houses,” replied Edison. Imagine, he told his audience: a home immune to fire, termites, mildew, and natural disasters.
Edison had been a believer in concrete for years. He had built a huge cement plant in New Jersey in 1899, and racked up a number of patents related to concrete and cement. In the wake of the earthquake, he became a full-fledged evangelist.
“It requires only one part of hydraulic Portland cement, mixed with three parts of sand and five parts of gravel . . . to make concrete as hard as adamant. I can put up a concrete building for about half the cost of a brick one,” Edison told a reporter for the San Francisco Call soon after the New York dinner. “I not only propose to construct the outside walls of my house with cement, but [also] the walls forming the interior divisions, the stairs, the mantels and fireplaces.” To top it off, he aimed to decorate the house
with concrete “scrolls and flowered designs.”42 Later, he promised to bring to market concrete furniture “that will make it possible for the laboring man to put furniture in his home more artistic and more durable than is now to be found in the palatial residences in Paris or along the Rhine.”43 He could and would make practically anything out of concrete, Edison insisted—even pianos.
Such was the prestige, even glamour, that concrete enjoyed after its literal trial by fire in San Francisco. Nowadays, when we think of concrete (if we think of it at all), we tend to associate it with ugliness and oppression—the featureless walls of prisons, the dreary, dehumanizing concrete jungle. But once upon a time it seemed almost miraculous, a manifestation of progress, the harnessing of the earth’s most basic materials to fulfill mankind’s most exalted ambitions. Edison’s home-building project fizzled out, and his concrete pianos never played a concert, but that didn’t slow concrete’s march to world domination.
“The rapid growth of reinforced concrete in public favor has been little short of marvelous. It is now used for nearly every form of structure for which timber, steel, or masonry is suitable,” declared Scientific American44 in 1906. Around the world, concrete office buildings, apartment blocks, hotels, dams, roads, statues, even ships were being built by the hundreds.45 “Are there no limits to the conquests of concrete?” marveled the Los Angeles Herald in 1908. “Every day this new-old building material, as hard as stone, as strong as steel, almost as cheap as lumber, and as plastic as clay is put to some new use . . . Steel has been king for a long time. Concrete seems in a fair way to usurp the throne.”46
Much like China and India today, the United States in those years was in the midst of twin population and urbanization booms. The country was adding an average of 1.5 million new citizens every year, and more and more Americans were moving to cities. The urban population nearly doubled between 1890 and 1910. By 1920, for the first time, more Americans lived in urban areas than on farms.47 Increasingly, their homes, their workplaces, and the roads they traveled between them were made of concrete.
