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NASA/Johnson Space Center

15 Secrets of Space Suit Design

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NASA/Johnson Space Center

It’s no secret that astronauts couldn’t survive the harsh environment of space without their suits. But there are plenty of things you might not know about how these suits go from concept to prototype to the final frontier. We asked Lindsay Aitchison, Space Suit Engineer at the Advanced Space Suit Design Group at NASA’s Johnson Space Center, to walk us through the process.

1. Designing space suits requires a particular set of skills.

And they’re not necessarily the ones you might think. Aitchison says the job requires both critical thinking and creativity. “You need to be detail-oriented and come up with a very precise test plan,” she says. “When you’re working with human test subjects, you have to design a test where you get constructive feedback on things that are squishy subjects, like comfort. How do you define comfort? You have to think about it from an engineering standpoint and engineer a suit to be comfortable.” Thinking creatively, Aitchison says, allows her to see how technologies from different fields might be incorporated into space suit design.

2. Suits are crafted for their missions.

When creating a new suit, Aitchison says NASA’s engineers must answer two questions to help them determine the structure of the suit: Where are you going and what are you doing?

The engineers start with where the astronaut is going, which falls into two categories: A micro-gravity location or a planetary environment, where they’ll have to walk (which determines how much mobility they’ll need in their suit). The engineers also consider things like how high radiation might be, the temperature ranges an astronaut will experience, and the risks of micro-meteoroids.

Next, engineers have to think about what astronauts will be doing on their missions: Will they be walking on their hands, as they would in micro-gravity, or walking on their feet, as they would on a planetary surface? Will they be digging with tools, or carrying everything on a toolbelt and performing tasks with their upper body? Will they need to be autonomous? “If you're on a planetary surface, that's pretty far from earth, so we're trying to develop more technologies so that you do autonomously EVAs,” Aitchison says, “whereas [on] space stations, you have a lot more direct contact with the flight control team, so we can offload some of those informatics and rely on flight control to help us.”

3. New Suits Need New Shoes.

EMU suit; photo courtesy of NASA.

The suit most people are familiar with is the Extravehicular Mobility Unit (EMU) suit. Because it's designed for use in micro-gravity—in which astronauts use their hands to move themselves around—to make repairs and modifications to the International Space Station (ISS), telescopes, and more during spacewalks, it needs to have mobility in the shoulders, hands, and arms. "You use the lower area [of the suit] for stability, so that way you have a stable work platform if you're at the end of a robotic arm," Aitchison says. "If it's too loosey goosey, you can't get any work done."

But new space suits, including the new Z-2, are being designed to go to planetary environments, so Aitchison and other designers spent a lot of time focusing on the design of the waist and hip joints—and the shoes. "This is the first time since Apollo that we need to have a walking boot, and when you're walking in different gravity fields, the way you walk changes," Aitchison says. "So we're focusing on how to design a boot to work with how you walk in, say, Martian or Lunar gravity environments. It's very different from the EMU, which is just a hard-soled boot."

To figure out what kind of shoe they'd want on their new suits, Aitchison did a number of walking tests with different suits in 2008. "We had [the suits] offloaded to different gravity weights, so if you were walking on a treadmill, it felt like you were walking at 3/8 gravity or 1/6 gravity because [a rig] was holding up the weight of the suit," she says. The team placed motion capture markers on the lower half of the suit to analyze how the foot, ankle, and hips were moving at different gravities. "We noticed through our testing that people tend to swing their hips up and sort of gallop [in different gravities], so if you pay attention to that, you can figure out where you need to have flexibility versus stiffness in the sole [of the shoe] to make that motion easier."

Though the team is still evaluating designs, Aitchison says that they're currently looking at a hiking boot sole. "It's pretty stiff in the forefoot but it's got some flexibility in the mid foot so you can sort of do those kneeling tasks."

4. The goal is to make new suits lighter.

Apollo suit; photo courtesy of NASA.

The EMU weighs a whopping 300 pounds (the astronauts, of course, don't feel that weight in microgravity). The Apollo suits, including backpacks, weighed 180 pounds on Earth and just 30 pounds on the Moon, by comparison—but, Aitchison says, "they didn't have a lot of mobility to them." The goal for new suits is to make them lighter while maintaining mobility. "When we add mobility, we're talking about adding hard elements like bearings, which make it very easy to work in a pressurized suit but come with a mass penalty," Aitchison says. "So we're trying to figure out low mass solutions for having those hard elements. We're looking at titanium because that saves us about 30 percent of mass on the bearings when we do that. And then [we're] looking at new types of composite materials for the upper torso material and for the hips and the brief section of the suit."

The new Z-2 will be about 20 pounds lighter than the EMU, "which doesn't seem like much," Aitchison acknowledges. "But again, we're adding in all the capability of the lower torso that we haven't had before."

5. Design starts by playing with old prototypes.

Once the where and the what are figured out, it’s time to get down to designing. The Advanced Space Suit Group has prototypes from the last 30 years of suits, as well as shuttle suits and suits from the Apollo era. “We start by testing those suits and understanding the different features,” Aitchison says. “What type of shoulder works best for what type of activity, different designs of the hips and boots and the style of entry. Do you want to have a zipper? All those things.” Playing with those features allows the engineers to sketch out what parts of different suits would be best for a particular mission.

6. NASA Scientists design the suits, but private companies make them.

Two-dimensional rendering of the "Technology" version of the Z-2 suit. Photo courtesy of NASA/Johnson Space Center.

Testing of the suits, and sketching up the designs, happens in house. But when it comes time to build, NASA turns its designs over to private companies. “We write the requirements and give the general concept of what we want built for us, and we have vendors that will build the suits for us, to the specifications that we write,” Aitchison says. The engineers work on one suit at a time, but since the start of Constellation in 2005, they’ve been getting prototypes every three to five years.

7. Certain parts of the suits are hand sewn.

In the Apollo era, space suits were sewn together by hand. You might think, with advances in technology, that this practice would have gone the way of the dodo, but that's not the case.

A little space suit anatomy: The innermost layer of the space suit, called the bladder—"think of that as basically being the balloon that holds all the air inside of it," Aitchison says—is sealed and welded together by a machine. On top of that is the restraint layer, which gives the bladder strength and structure. "It makes sure [the bladder] bends to that specific location and it takes all of the loads of the suit to protect that bladder from too much force when you bend your elbow or if you put pressure onto it," Aitchison says.

The restraint layer is the part of the suit that's still hand stitched. "There is a room full of sewers with different types of sewing machines, depending on what part of the suit they're stitching, and they can do some very precision sewing by hand," Aitchison says. "Like a 16th of an inch in some places, and they are incredible at that." The sewers use specific types of thread for certain locations, depending on whether they need more strength or elasticity in that section.

8. But they're still cutting edge.

Engineers used 3D human laser scans and 3D-printed hardware to develop and size the Z-2 suit—the first time that's ever been done.

9. Suits are allowed to leak.

But not a lot. According to Aitchison, the whole suit is allowed to leak a maximum of 100 SCCM (standard cubic centimeters per minute). To ensure the suit doesn't leak, and that it's meeting the requirements determined by the designers, its parts are rigorously tested during the fabrication process. Seam allowances are measured with rulers, and samples are purposely destroyed to ensure they meet the required strength characteristics. "[Testers] pull out a machine to see how much force it takes to rip either the seam or the fabric itself," Aitchison says.

When the designers receive the full suit, it, too, undergoes testing. "We do structural and linkage testing, which means we inflate the suit to 1.5 times its regular operating pressure—which is 4.3 PSI when we're doing a space walk—to make sure that it's structurally sound, we're not seeing any windowing at the seams or have any leaks," Aitchison says. "And then after we do the structural [test], we go back down to regular operating pressure and redo the leak check."

10. There are no custom space suits.

It's not cost effective to build one suit for every crewmember. Instead, the suits are constructed using a modular system, which is part of why they're so bulky. "When you have mix and match components, we tend to make it a little bit larger, so that we can fit a wider population of people," Aitchison says. "We have different components—basically small, medium, large sorta fit—so we can mix and match components between different sized crew. That way it helps us with logistics and with redundancy on the space station, too." (Currently, the space station has enough components for four full Extravehicular Mobility Unit, or EMU, suits, as well as a number of replacement parts.) Having a modular system also makes things easier with repairs: If one part breaks, engineers can simply replace the part instead of building a whole new suit.

11. Designers focus on one suit at a time.

Given all the testing and design requirements that go into a suit, it's probably not surprising that engineers take it one suit at a time. "We want to understand what does and doesn't work before we build our next iteration," Aitchison says. From concept to design to prototype to testing, "it takes a long time to build a new suit. It takes over a year." Fabrication on the Z-2 suit will begin this month; it will be completed in August, at which point, testing will begin.

12. Astronauts must don a number of layers before they even put on their suits.

That scene from Gravity where Sandra Bullock pulls off her EMU suit and emerges in nothing but a tank top and her undies? Pure bunk. Real astronauts wear several layers under their suits.

First comes a maximum absorbency garment, or MAG, "which is basically a diaper with extra absorption in it," Aitchison says. "That's your waste management system." Over that are comfort undergarments, form-fitting long johns that keep an astronaut comfortable while he or she is wearing the liquid cooling garment. "It provides skin cooling when you're inside your suit and you're working really hard," Aitchison says. "We don't want you to build up a sweat, so we have cold water running in tubes all over your body that pick up heat from your skin and reject it back out to space."

13. There are ways to make a pressurized suit.

Photo courtesy of MIT

Anyone going into space needs to have pressure on their body to keep it functioning normally; the minimum PSI required for bodily functions like inflating the lungs and keeping the blood flowing is 2.5 PSI. (A little more than that, Aitchison points out, is even better.) To accomplish that, astronauts need either a gas-pressurized suit—which is what NASA uses—or a suit that uses mechanical counter pressure (MCP), like the one developed at MIT (above). "You can kind of think of [MCP] as a very tight wet suit," Aitchison says. "It's got to create the same amount of pressure that we get from the gas around us just by pressing on the skin with the suit itself."

NASA looked at a mechanical pressure suit, developed by Dr. Paul Webb, in the 1970s; it was called the Space Activity Suit. Though it worked very well, it took multiple hours—and the help of several people—to put on. That's not the only drawback to MCP. "The other thing you have to worry about is making sure that you have even pressure across your skin at all different positions," Aitchison says. "Places that are concave, or places that change from being flat to concave—the palms of your hands, the backs of your elbows, the knee, the groin—as you move, the shape of those places change. You need to make sure you develop materials that will stick into those contours and move with the change of shape. So there are a lot of challenges in terms of having the technology that's going to help us do exploration in the next 5 to 10 years. Gas pressurized suits are the way we're going to get there."

14. The Z-2 Will be Pretty Small.

Z-1 Space suit. Photo courtesy of NASA/Johnson Space Center.

It will actually be one of the smallest suits made for exploration. "Previously, on the Z-1, we had the big 13-inch dome," Aitchison says. "That works well for large men, but it doesn't have to be that big for smaller females. So shrinking that shrinks down the rest of the suit too. We looked at the current astronaut population and we tried to design a suit that would fit everyone in the bottom 40 percent in terms of their size." The goal of the Z-2 is to design a suit that will fit everyone from the 5th percentile female and to the 99th percentile male—a huge size range.

15. And you can vote on what it will look like.

Z-2 renderings courtesy of NASA/Johnson Space Center.

NASA's last suit design, the Z-1, looked a little bit like Toy Story character Buzz Lightyear (an accident, according to Aitchison). "There was a lot of talk about it, and we wanted to build on that momentum with this suit just to get people asking questions and wanting to know more about it," Aitchison says. "So we came up with this idea to do a voting website for it."

The engineers worked with fashion students at Philadelphia University to come up with different looks for the suit, which was a very different process than what the engineers were used to. "They definitely take a different approach, coming from a fashion background," Aitchison says. "We had to fill out mood boards with different characteristics, whether it was a patriotic theme or a traditional theme or a science and technology theme. We started out with 12 characteristics and we had to narrow it down to what we thought represented us." Based on that, the engineers and the student designers came up with three concepts: Biomimicry, Technology, and Trends in Society. You can vote for your favorite design here.

For now, the designs are purely aesthetic, but Aitchison can see real-life applications for the bioluminescence in the Biomimicry suit, for example. "When we go to other planetary surfaces, if we're working in environments where we have constant day/night cycles, it might be a cool way to do the crew identifier," she says. "Right now we have fabric stripes along the side and upper arm to indicate who's who to different color stripes for each crew member. [Bioluminescence] could be a unique way to do that that would actually be helpful on a planetary surface."

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Mabel Livingstone/Hulton Archive/Getty Images
12 Surprising Facts About Bela Lugosi
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Mabel Livingstone/Hulton Archive/Getty Images

On October 20, 1882—135 years ago today—one of the world's most gifted performers was born. In his heyday, Bela Lugosi was hailed as the undisputed king of horror. Eighty-five years after he first donned a vampire’s cape, Lugosi's take on Count Dracula is still widely hailed as the definitive portrayal of the legendary fiend. But who was the man behind the monster?


To the chagrin of his biographers, the details concerning Bela Lugosi’s youth have been clouded in mystery. (In a 1929 interview, he straight-up admitted “for purposes of simplification, I have always thought it better to tell [lies] about the early years of my life.”) That said, we do know that he was born as Béla Ferenc Dezső Blaskó on October 20, 1882 in Lugoj, Hungary (now part of Romania). We also know that his professional stage debut came at some point in either 1901 or 1902. By 1903, Lugosi had begun to find steady work with traveling theater companies, through which he took part in operas, operettas, and stage plays. In 1913, Lugosi caught a major break when the most prestigious performing arts venue in his native country—the Budapest-based National Theater of Hungary—cast him in no less than 34 shows. Most of the characters that he played there were small Shakespearean roles such as Rosencrantz in Hamlet and Sir Walter Herbert in Richard III.


The so-called war to end all wars put Lugosi’s dramatic aspirations on hold. Although being a member of the National Theater exempted him from military service, he voluntarily enlisted in the Austro-Hungarian Army in 1914. Over the next year and a half, he fought against Russian forces as a lieutenant with the 43rd Royal Hungarian Infantry. While serving in the Carpathian mountains, Lugosi was wounded on three separate occasions. Upon healing from his injuries, he left the armed forces in 1916 and gratefully resumed his work with the National Theater.


In December 1920, Lugosi boarded a cargo boat and emigrated to the United States. Two years later, audiences on the Great White Way got their first look at this charismatic stage veteran. Lugosi was cast as Fernando—a suave, Latin lover—in the 1922 Broadway stage play The Red Poppy. At the time, his grasp of the English language was practically nonexistent. Undaunted, Lugosi went over all of his lines with a tutor. Although he couldn’t comprehend their meaning, the actor managed to memorize and phonetically reproduce every single syllable that he was supposed to deliver on stage.


The year 1927 saw Bela Lugosi sink his teeth into the role of a lifetime. A play based on the novel Dracula by Bram Stoker had opened in London in 1924. Sensing its potential, Horace Liveright, an American producer, decided to create an U.S. version of the show. Over the summer of 1927, Lugosi was cast as the blood-sucking Count Dracula. For him, the part represented a real challenge. In Lugosi’s own words, “It was a complete change from the usual romantic characters I was playing, but it was a success.” It certainly was. Enhanced by his presence, the American Dracula remained on Broadway for a full year, then spent two years touring the country.

Impressed by its box office prowess, Universal decided to adapt the show into a major motion picture in 1930. Horror fans might be surprised to learn that when the studio began the process of casting this movie’s vampiric villain, Lugosi was not their first choice. At the time, Lugosi was still a relative unknown, which made director Tod Browning more than a little hesitant to offer him the job. A number of established actors were all considered before the man who’d played Dracula on Broadway was tapped to immortalize his biting performance on film.


The recent Twilight phenomenon is not without historical precedent. Lugosi estimated that, while he was playing the Count on Broadway, more than 97 percent of the fan letters he received were penned by female admirers. A 1932 Universal press book quotes him as saying, “When I was on the stage in Dracula, my audiences were composed mostly of women.” Moreover, Lugosi contended that most of the men who’d attended his show had merely been dragged there by female companions.   


Released in 1931, Dracula quickly became one of the year's biggest hits for Universal (some film historians even argue that the movie single-handedly rescued the ailing studio from bankruptcy). Furthermore, its astronomical success transformed Lugosi into a household name for the first time in his career. Regrettably for him, though, he’d soon miss the chance to star in another smash. Pleased by Dracula’s box office showing, Universal green-lit a new cinematic adaptation of Mary Shelley’s Frankenstein. Lugosi seemed like the natural choice to play the monster, but because the poor brute had few lines and would be caked in layers of thick makeup, the actor rejected the job offer. As far as Lugosi was concerned, the character was better suited for some “half-wit extra” than a serious actor. Once the superstar tossed Frankenstein aside, the part was given to a little-known actor named Boris Karloff.

Moviegoers eventually did get to see Lugosi play the bolt-necked corpse in the 1943 cult classic Frankenstein Meets the Wolf Man. According to some sources, he strongly detested the guttural scream that the script forced him to emit at regular intervals. “That yell is the worst thing about the part. You feel like a big jerk every time you do it!” Lugosi allegedly complained.


It’s often reported that the two horror icons were embittered rivals. In reality, however, Karloff and Lugosi seemed to have harbored some mutual respect—and perhaps even affection for one another. The dynamic duo co-starred in five films together, the first of which was 1934’s The Black Cat; Karloff claimed that, on set, Lugosi was “Suspicious of tricks, fearful of what he regarded as scene stealing. Later on, when he realized I didn’t go in for such nonsense, we became friends.” During one of their later collaborations, Lugosi told the press “we laughed over my sad mistake and his good fortune as Frankenstein is concerned.”

That being said, Lugosi probably didn’t appreciate the fact that in every single film which featured both actors, Karloff got top billing. Also, he once privately remarked, “If it hadn’t been for Boris Karloff, I could have had a corner on the horror market.”


In 1935, Lugosi was named Honorary President of the Los Angeles Soccer League. An avid fan, he was regularly seen at Loyola Stadium, where he’d occasionally kick off the first ball during games held there. Also, on top of donating funds to certain Hungarian teams, Lugosi helped finance the Los Angeles Magyar soccer club. When the team won a state championship in 1935, one newspaper wrote that the players were “headed back to Dracula’s castle with the state cup.” [PDF]


Lugosi's fourth wife, Lillian Arch, claimed that Lugosi maintained a collection of more than 150,000 stamps. Once, on a 1944 trip to Boston, he told the press that he intended to visit all 18 of the city's resident philately dealers. “Stamp collecting,” Lugosi declared, “is a hobby which may cost you as much as 10 percent of your investment. You can always sell your stamps with not more than a 10 percent loss. Sometimes, you can even make money.” Fittingly enough, the image of Lugosi’s iconic Dracula appeared on a commemorative stamp issued by the post office in 1997.


The role of Count Dracula in this 1948 blockbuster was nearly given to Ian Keith—who was considered for the same role in the 1931 Dracula movie. Being a good sport, Lugosi helped promote the horror-comedy by making a special guest appearance on The Abbott and Costello Show. While playing himself in one memorable sketch, the famed actor claimed to eat rattlesnake burgers for dinner and “shrouded wheat” for breakfast.


Toward the end of his life, Lugosi worked on three ultra-low-budget science fiction pictures with Ed Wood, a man who’s been posthumously embraced as the worst director of all time. In the 1953 transvestite picture Glen or Glenda?, Lugosi plays a cryptic narrator who offers such random and unsolicited bits of advice as “Beware of the big, green dragon who sits on your doorstep.” Then came 1955’s Bride of the Monster, in which Lugosi played a mad scientist who ends up doing battle with a (suspiciously limp) giant octopus.

Before long, Wood had cooked up around half a dozen concepts for new films, all starring Lugosi. At some point in the spring of 1956, the director shot some quick footage of the actor wandering around a suburban neighborhood, clad in a baggy cloak. This proved to be the last time that the star would ever appear on film. Lugosi died of a heart attack on August 16, 1956;  he was 73 years old.

Three years after Lugosi's passing, this footage was spliced into a cult classic that Wood came to regard as his “pride and joy.” Plan 9 From Outer Space tells the twisted tale of extraterrestrial environmentalists who turn newly-deceased human beings into murderous zombies. Since Lugosi could obviously no longer play his character, Wood hired a stand-in for some additional scenes. Unfortunately, the man who was given this job—California chiropractor Tom Mason—was several inches taller than Lugosi. In an attempt to hide the height difference, Wood instructed Mason to constantly hunch over. Also, Mason always kept his face hidden behind a cloak.


Although Lugosi resented the years of typecasting that followed his breakout performance in Dracula, he asked to be laid to rest wearing the Count’s signature garment. Lugosi was buried under a simple tombstone at California's Holy Cross Cemetery.

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The First Known Uses of 6 Common Typographic Symbols
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Many of the most common symbols on our keyboards have fascinating origin stories. Some, such as the zero, we now take for granted—yet the idea of denoting an absence of value was not present in Western mathematics until introduced from the East. Other symbols, such as the hashtag or at-sign, had a variety of uses until the internet ushered in a new way of communicating and fixed them with the meanings we know today. Below are six examples of the first known usage and subsequent history of some of the most common typographic symbols.

1. AT SIGN // @

The @ (or at-sign) is usually dated to 1536 in a letter from a Florentine merchant, Francesco Lapi, who used it to mean a unit of wine called “amphorae.” But a Spanish researcher claims to have found an even earlier usage in a 1448 document, where the symbol also referred to a unit of measurement (even today, Spaniards call the @ symbol arroba, which is also a unit of weight, and some other Romance languages have similar dual meanings). Either way, the researchers think that the symbol then moved to Northern Europe, where it eventually gained the meaning of “at the price.” Other explanations have also been offered, but whatever the exact root of the symbol, its meaning eventually became known as shorthand for at, and it was generally used in written financial transactions—for example, in noting “Bob sells James 4 apples @ $1.”

The sign had largely fallen out of use by the early 1970s, when computer scientist Ray Tomlinson was working at what is now BBN Technologies, in Cambridge, Massachusetts. Tomlinson, who was working for the government on a forerunner of the internet, was trying to figure out how to address messages sent from one computer to another when he noticed the little-used @ on his computer keyboard, and used it to send a prototype email. This precedent was soon adopted as the internet developed, and the at-sign is now, of course, central to our lives.

2. ZERO // 0

The absence of a value is a complex concept, one that many ancient civilizations struggled with. The idea of a zero ultimately came to the West from the mathematicians of India, where, as in a few other cultures, zero was initially used as a placeholder, for example to indicate a lack of units, as in the number 101.

The earliest surviving usage of a zero in India has been traced to an ancient mathematical text known as the Bakhshali manuscript, which is held at Oxford’s Bodleian Library. In September 2017, radiocarbon dating indicated that the manuscript was produced as early as the 3rd or 4th century—providing us with the first known usage of zero some 500 years earlier than previously thought. As Oxford’s Bodleian Library says, “the symbol in the Bakhshali manuscript is particularly significant for two reasons. Firstly, it is this dot that evolved to have a hollow centre and became the symbol that we use as zero today. Secondly, it was only in India that this zero developed into a number in its own right, hence creating the concept and the number zero that we understand today."

The manuscript itself was discovered buried in a field in 1881 in what is today Pakistan. Written on 70 delicate leaves of birch bark, historians think it represents a training manual for Silk Road traders, teaching them concepts of arithmetic.

3. HASHTAG // #

Hashtag on an old typewriter key

The origin of the hashtag (or pound sign as it's traditionally known in the U.S.) comes from scribes writing shorthand for the Latin libra pondo, which translates as "pound by weight." The abbreviation they used was lb, which was sometimes misread as 16. So, scribes took to drawing a line through the top of the two letters, which over time developed into the now familiar #. In the 1960s, the pound sign was chosen by Bell Laboratories to be a function key on their newly designed telephone keypad. (The Bell Labs team fondly nicknamed the symbol the “octothorpe,” possibly in honor of athlete Jim Thorpe.) Fast-forward to 2007, when early Twitter users wanted to be able to group and filter their feeds, so developer Chris Messina suggested they appropriate the method used in IRC (Internet Relay Chat) whereby users employed the pound sign or "hashtag" to signpost what they were chatting about. (Programmers knew the symbol as the hash, which was now being used to "tag" content.) This simple method soon caught on, and today the hashtag has become indelibly linked to the rise of social media.

4. ELLIPSIS // …

Originally, periods of silence were marked textually with a series of hyphens, but today the symbol of choice is the , a.k.a. the ellipsis. Dr. Anne Toner of Cambridge University spent years researching the ellipsis and finally discovered what she thinks is its first use—an English translation of Roman dramatist Terence’s play Andria printed in 1588. Although the play used hyphens instead of dots, the general idea caught on rapidly. (Toner notes that although there are only four “ellipses” in the 1588 translation, there are 29 in the 1627 version.) By the 18th century, dots started to replace the dashes, which an assistant professor from Southeastern University suggests may be connected to a medieval piece of punctuation called subpuncting or underdotting, which generally indicated something was incorrectly copied.


Ampersand symbol on an old metal block

The ampersand originated in Latin when the word et (meaning and) was written in cursive script as a ligature (in which one or more letters are written together as a single glyph). One of the earliest examples was found daubed in graffiti on the walls of a house in Pompeii, where it was preserved by the eruption of Vesuvius in 79 CE. By the 8th century the ampersand became a recognizably distinct character, but the word ampersand did not come into use until the late 18th/19th century, when English school children would recite "and per se and" meaning “and by itself means and” to help remember the symbol (per se being Latin for "by itself"). One of the most thorough investigations into the typographic history of the ampersand comes courtesy of German graphic designer Jan Tschichold, who in 1953 published The am­persand: its ori­gin and de­vel­op­ment, in which he collected numerous examples of the ampersand from the 1st century onwards, visually charting its developing form.

6. PLUS SIGN // +

A variety of ceramic plus signs

The plus sign used for addition in mathematics likely derives from a shorthand ligature for the Latin et meaning “and” and was probably in use for a long time before a surviving example appeared in print. One candidate for the earliest surviving usage is in French philosopher and polymath Nicole Oresme's Algorismus proportionum, a manuscript handwritten between 1356 and 1361, although scholars debate whether it's a true plus symbol. The first use of a plus sign in a printed book is more definitive, and can be found in a 1489 edition of Johannes Widmann’s Mercantile Arithmetic. Widmann also uses the minus sign for the first time in print in this volume—although both plus and minus signs relate not to addition and subtraction but to surpluses and deficits in business accounting. After this usage, the plus sign began to appear more frequently in German mathematical texts, and first appeared in an English text in 1557 in Robert Recorde’s The Whetstone of Witte—which also introduced the equals sign.


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