So you know you’re looking at two very different styles of dress, here. But precisely what decades? When did that waistline move back down? What details are the defining touches of their era? How long were women actually walking around with bustles on their backsides?

Lydia Edwards’s How to Read a Dress is a detailed, practical, and totally beautiful guide to the history of this particular form of clothing from the 16th to the 20th centuries. It tracks the small changes that pile up over time, gradually ******* until your great-grandmother’s closet looks wildly different than your own. As always, fashion makes for a compelling angle on history—paging through you can see the shifting fortunes of women in the Western world as reflected in the way they got dressed every morning.

Of course, it’ll also ensure that the next lackadaisically costumed period piece you watch gives you agita, but all knowledge has a price.

I spoke to Edwards about how exactly we go about resurrecting the history of an item that’s was typically worn until it fell apart and then recycled for scraps; our conversation has been lightly trimmed and edited for clarity.

The title of the book is How to Read a Dress. What do you mean by “reading” a dress?

Basically what I mean is, when you are looking at a dress in an exhibition or a TV show, reading it in terms of working out where the inspirations or where certain design choices come from. Being able to look at it and recognize key elements. Being able to look at the bodice and say, Oh, the shape of that is 1850s, and the design relates to this part of history, and the patterning comes from here. It’s looking at the dress as an object from the top down and being able to recognize different elements—different historical elements, different design elements, different artistic elements. “Read” is probably the best word to use for that kind of approach, if that makes sense.

It must send you around the bend a little bit, watching costume adaptations where they’re a bit slapdash. The one I think of is the Keira Knightley Pride and Prejudice, which I actually really enjoy, but I know that one’s supposed to have all over the place costuming-wise.

Yeah, it does. I mean, I love the BBC Pride and Prejudice one, because they kept very specifically to a particular era. But I can see what they did with the Keira Knightley one—they were trying to keep it 1790s, when the book was written, as opposed to when it was published. But they’ve got a lot of kind of modern influences in there and they’ve got a lot of influences from 30, 40 years previously, which is interesting to an audience and gives an audience I suppose more frames of reference, more areas to think about and look at. So I can see why they did that. But it does make it more difficult if you’re trying to accurately decode a garment. It’s harder when you’ve got lots of different eras going on there, but it makes it beautiful and interesting for an audience.

The guide spans the 16th to the 20th century. Why start with the 16th century?

Well, partly because it’s where my own interest starts, in terms of my research and the areas I’ve looked at. But more importantly in terms of audience interest, we get a lot of TV shows, a lot of films in recent years—things like The Tudors—that type of era seems to be something that people are interested in. That time is very colorful and very interesting to people.

And also because in terms of thinking about the dress as garment, obviously people wore dresses in medieval times, but in terms of it being something that specifically women wore, distinct from men’s clothes, I really think we start to see that more in the 15th, 16th century onwards.

Where do you go to get the historical information to put together a book like this? What do you use as your source material? Because obviously the thing about clothing is that it has to stand up to a lot of wear and tear and a lot of it doesn’t survive.

This is the other thing about the 16th century stuff—there’s so little surviving. That’s why that chapter was a lot shorter and also that’s why I used a lot of artworks rather than surviving garments, just because they don’t exist in their entirety.

But wherever possible, you go to the garments themselves in museum collections. And then if that’s proving to be difficult, you go to artworks or images, but always bearing in mind the artist will have had their own agenda, so they won’t necessarily be accurate of what people were actually wearing. So then you have to go and look up written source material from the time—say, diaries. I like using letters that people have written to each other over the centuries, describing dress and what they were wearing on a daily basis. Novels can be good, as well.

Also the scholarship that has come before, the secondary sources, works by people like Janet Arnold, Aileen Ribeiro. Really well researched scholarly books where people have used primary sources themselves and put their own interpretation on it can be really, really helpful. Although you take some of it with a pinch of salt, and you put your own interpretation on there, as well.

But always to the dress itself wherever possible.

What are some of the challenges you face, or the constraints on our ability to learn about the history of fashion?

Well, the very practical issue of trying to see garments—some of them I did see here in Australia, but a lot of them were in the States, in Canada, in New Zealand, so it’s hard to physically get there to see them. And often, even when you can get to the museum, garments are out on loan to other exhibitions or other museums. That’s a practical consideration.

But also, especially when I’m talking about using artworks and things, which can be really helpful when you’re researching, but as I’ve said they do come from a place where there’s more interpretations and more agendas. So if someone’s done a portrait and there’s a beautiful 1880s dress in it, that could have been down to the whims of the person who was wearing it, or the artist could have changed significantly the color or style to suit his own taste. Then you have to do extra research on top of that, to make sure that what you are seeing is representative.

It’s a fascinating area. There’s a lot of challenges, but for me, that’s what makes it really exciting as well. But it’s really that question of being able to trust sources and knowing what to use and what not to use in order to make things clear for the audience.

Obviously many of these dresses were very expensive and took a lot of labor and it wasn’t fast fashion—people didn’t just give it away or toss it when it fell out of season. A lot of times, you did was you remade it. When you’re looking at a dress that’s been remade, how do you extract the information that you need as a historian out of it?

I love it when something like that comes up. I’ve got a couple of examples in the book.

Well, it can be quite challenging, because often when you’re first looking at a piece it’s not obvious that it’s been remade. But if you’re lucky enough to look inside it and actually hold it and turn it round different angles, there’ll be things like the placement of a seam, or you’ll see that the waist has been moved up or down according to the fashion. And that’s often obvious when you’re looking inside. You can see the way the skirt’s been attached. Often you can tell if a skirt’s been taken off and then reattached using different pleats, different gatherings; that can give you a hint that it’s then been remade to fit in with a different fashionable ideal.

One of the key ways is fabric. You can often see, especially in early 19th century dresses when they’ve been made of these beautiful 18th century silks and brocades. That’s nice because it’s the first obvious clue that something’s been remade or that an old dress has been completely taken apart and it’s just the fabric that’s been used. I find it particularly interesting when the waist has been moved or the seams have been taken off or re-sewn in a different shape or something like that. It can be subtle but once your knowledge base grows, that’s one of the most fascinating areas that you can look at.

You page through the book and you watch these trends unfold and there are occasional sea changes will happen fairly quickly, like when the Regency style arises. But how much change year-to-year would a woman have seen? How long would it take, just as a woman getting dressed in the morning, to see styles just radically alter? Would you even notice?

Well, this is the thing—I think it’s very easy, when we’re looking back, to imagine that in 1810 you’d be wearing this dress and then all the frills and the frouf would have started to come in the late 1810s and the 1820s, and suddenly you would have had a whole new wardrobe. But obviously, unless you were the very wealthiest women and you had access to dressmakers who had the absolute newest patterns and newest fabrics then no, you wouldn’t have seen a massive change. You wouldn’t have afforded to be able to have the newest things as they came in. You would have maybe remade dresses to make them maybe slightly more in line with a fashion plate that you might have seen, but you wouldn’t have had access to new information and new fashion plates as soon as they came. To be realistic, there would have been very little change on a day to day level.

But I think also, for us now—it’s hard to see it without hindsight, but we feel like we’re fairly fluid in wearing the same kind of styles, but obviously when we look back in 20 years, we’ll look at pictures of us and see greater changes than we’re now aware. Because it happens on a slow pace and it happens on such a subconscious level in some ways.

But actually, yeah, it’s to do with economics, it’s to do with availability. People living in towns where they couldn’t easily get to cities—if you were living in a country town a hundred miles away from London, there’s no way that you would have the resources to see the most recent fashion plates, the most recent ideas that were developing in high society. So it was a very slow process in reality.

If you have a lot of money you can change out your wardrobe quicker and wear the latest styles. And so the wealthiest people, their clothes were what in a lot of case stood the best chance of surviving and being in modern collections. So how do we know what working women would have worn or what middle class women would have worn?

Yeah, this is hard. I do have some more middle class examples, because we’re lucky in that we do have quite a few that have survived, especially in smaller museums and historical collections, where people have had clothes sitting in their attics for years and have donated them, just from normal families over the years.

But, working women, that’s much more difficult. We’re lucky from the 19th century because we have photographic evidence. But really a lot of it will come down to written descriptions, mainly letters, diaries, not necessarily that the people themselves would have kept, but there’s examples of people that worked in cotton mills, for instance, and people that ran the mills and their families and wives and friends who had written accounts of what the women there were wearing. Also newspaper accounts, particularly of people who would go and do charity work and help the poor. They often wrote quite detailed descriptions of the people that they were helping.

But in terms of actual garments, yeah, it’s very difficult. Certainly 18th century and before, it’s really, really hard to get hold of anything that gives you a really good idea of what they wore. But in the 18th century—it’s quite interesting, because then we get examples of separate pieces of clothing worn by the upper classes, like a skirt with a jacket, which was actually a lower middle class style initially and then it became appropriated by the upper classes. And then it became much fancier and trimmed and made in silks and things. So then, we can see the inspiration of the working classes on the upper classes. That’s another way of looking at it, although of course that’s much more problematic.

It’s interesting how in several cases you can see broader historical context, or other stories happening through clothes. Like you point out that the rise of the one-piece dresses is due to the rise of mantua makers, who were women who were less formally trained who were suddenly making clothing. Are there any other interesting stories like that, that you noticed and thought were really fascinating?

There’s a dress in the book that a woman made for her wedding. I think she was living on her own, or she was living with a servant and her mother or something. She made the dress and then turned up to her wedding and traveled quite a long way to get there, and when she arrived, the groom and all the guests weren’t there. There was nobody. So she went away and came back again a week later, and everyone was there. And the reason that no one was there before was that a river had flooded in the direction that they were all coming from. She had obviously no way of finding out about this until after the fact, and we have this beautiful dress that she spent ages making and had obviously gone to a lot of effort to try and work out what the latest styles were, to incorporate it into her wedding dress.

Things like that, I find really interesting, because they talk so much about human and social history as well as fashion history, and the garment is the main way we have of keeping these stories alive and remembering them and looking into the kind of life and world these people lived, who made these garments.

Over the centuries, how does technology affect fashion? Obviously, we think of the industrial revolution as really speeding up the pace of fashion. But are there other moments in the history of fashion where technology shapes what women end up wearing?

One example is where I talk about the Balenciaga dress from the early 1950s—with a bubble hem and a hat and she would have worn these beautiful pump shoes with it—with the introduction of the zipper. Which just made such a huge difference, because it suddenly meant you’d have ease and speed of dressing. It meant that you didn’t have to worry about more complicated ways of fastening a garment. I think the zipper made a massive change and also in terms of dressmaking at home, it was a really quick and simple way that people had of being able to create quite fashionable styles on a budget and with ease and speed at home.

Also, of course, once women’s dress started to become simpler and they did away with the corset and underwear became a lot less complicated, that made dressing a lot easier, that made the introduction of the bias cut and things that sit very closely to the natural body much more widely used and much more fashionable.

I would say the introduction of machine-made lace as well, particularly from the late 19th, early 20th century onwards where it was so fashionable on summer dresses and wedding dresses. It just meant that you could so much more easily add this decadent touch to a garment, because lace would have been so much more expensive before then and so time-consuming to make. I think that made a huge difference in ordinary women being able to attain a kind of luxury in their everyday dress.

That actually makes me think of something else I wanted to ask you, which is you point out in your intro the way we casually use this word “vintage.” I think about that with lace. Lace is described as being a “vintage” touch but it’s very much this question of when, where, who, why—it’s a funny term when you think about it, the way we use it so casually to describe so much.

Oh, yes. It’s crazy. I used to work in a wedding dress shop and I used to make historically inspired wedding dresses and things. And brides used to come in and say, “Oh, I want something vintage.” But they didn’t really know what they meant. Usually what they meant is they wanted something with a bit of lace on it, or with some sort of pearls or beading. I think it’s really inspired by whatever is trending at the time. So, you know, Downton Abbey became vintage. I think ‘50s has always been kind of synonymous with the word vintage. But what it means is huge,

The 9.6 million followers who tune in to watch Miranda Kerr having her hair done on Instagram — for this is how models spend most of their time — were treated to a rather more interesting sight last Thursday: a black and white photograph of a whacking great diamond ring.

Across it was the caption “Marry me!” and a twee animation of the tech mogul Evan Spiegel on bended knee. Underneath Kerr had typed “I said yes!!!” and an explosion of heart emojis.

A spokesman for Spiegel, founder of the Snapchat mobile app, who is 26 to Kerr’s 33 and worth $US 2.1 billion to her $US 42.5 million , revealed “they are very happy”.

At first, the marriage seems an unlikely combination: a man so bright he founded Snapchat while still at Stanford University, becoming one of the world’s youngest self-made billionaires by 22, and a Victoria’s Secret model who was previously married to the Pirates of the Caribbean star Orlando Bloom (she allegedly had a fling with pop brat Justin Bieber, leading Bloom to punch Beebs in a posh Ibiza restaurant).

Perhaps the union indicates that there is more to Kerr than we thought. More likely, it reveals something about Spiegel — and the way the social status of “geeks” has changed.

Since Steve Jobs made computers cool and Millennials started living online, nerds are king. Even coding is **** enough for the model Karlie Kloss, singer will.i.am and actor Ashton Kutcher to learn it. Silicon Valley has become the new Hollywood, as moguls and social media barons take over from film stars and sportsmen not just on rich lists, but as alpha men.

Being a co-founder of a company is this decade’s equivalent to being a rock star or a chef. And, if their attractiveness to models and actresses proves anything, then being a Twag — tech wife or girlfriend — is a “thing”. Sources tell me Twags are also known as “founder-hounders” because they like to date the creators of start-up companies.

Actress Talulah Riley was an early adopter. She started dating the PayPal founder Elon Musk in 2008. Riley, then fresh from starring in the St Trinian’s film, met Musk in London’s Whisky Mist nightclub after he had delivered a lecture at the Royal Aeronautical Society. I interviewed her shortly afterwards and she told me they had spent the evening talking about “quantum physics”. A month later they were engaged. Their on-again-off-again marriage lasted six years before she filed for divorce again in March. Currently Musk, worth an estimated $US 12.7 billion and focused on Tesla cars, is said to be “spending a lot of time” with Johnny Depp’s estranged wife, Amber Heard.

Model Lily Cole dated the Twitter founder Jack Dorsey in 2013. Later she had a son with Kwame Ferreira, founder of the digital innovation agency Kwamecorp. Actress Emma Watson is going out with William Knight, an “adventurer” who has an incredibly boringly sounding job as a senior manager at Medallia, a software company. Allison Williams, Marnie in the HBO television show Girls, is married to Ricky Van Veen, co-founder of College Humor website.

Could it be that these women are onto something? Dating a bro certainly has its appeal. They are innovative: how else would they invent apps that deliver cheese toasties or match singles based on their haircuts? They are risk-takers who must be charismatic enough to inspire investors and attract crowd-funding. They may not be gym-fit, but they are mathletes who can do your tax bill. They are animal lovers: every start-up is dog friendly. And they are fun: who would not want to date somebody with a ball pool in their office?

There is a saying about dating in Silicon Valley: the odds are good but the goods are odd. Nerds are notorious for peculiar chat-up lines and normcore clothes. Still, if geeks can be awkward, that is part of their charm. Keira Knightley, complaining that Silicon Valley was all men in hoodies and Crocs, described how one gave her his card, saying she should get in touch if she wanted to see a spaceship.

One Vogue writer recalled a Silicon Valley man messaging her via a dating app, in which he noted: “In 50 per cent of your photos you’re holding an iPhone. It may interest you to find out that I invented the iPhone. More accurately I was an engineer on the original iPhone . . .”

Most promisingly, some guys are astoundingly rich. It is suggested Kerr’s engagement ring is a 2.5-carat diamond worth around dollars 55,000. She has already moved into Spiegel’s dollars 12m LA pad. Between his money and her Victoria’s Secrets bridesmaids, no wonder sources claim they are planning an “extravagant wedding”.

It might rival even the Napster founder Sean Parker’s $US10m performance-art bash. He married songwriter Alexandra Lenas in a canopy among Big Sur’s redwoods decorated to look like an enchanted forest. Some 350 guests wore Tolkienesque costumes created by The Lord of the Rings costume designer Ngila Dickson. They sat on white fur rugs and were given bunnies to pet. Presumably rabbit babysitters were on hand when the disco started.

If such fantasies inspire you to become a Twag, the great news is you do not have to be a supermodel to be in with a chance. Such is the dearth of single women in Silicon Valley that one dating site, Dating Ring, crowdfunded a plane to fly single women to Palo Alto from New York.

Be warned, though: guys are single because they are married to the job.

No wonder most meet their partners at college or work — the Facebook chief executive Mark Zuckerberg met his wife, Priscilla Chan, at Harvard.

The Instagram co-founder Kevin Systrom met girlfriend Nicole Schuetz at Stanford. Melinda met Bill Gates when, in 1987, they sat next to each other at an Expo trade-fair dinner. “He was funnier than I expected him to be,” she said.

Kerr began dating Spiegel in 2014 after meeting him at a Louis Vuitton dinner in New York. You can bet he was networking. Shortly after Louis Vuitton showcased their cruise collection in a Snapchat story. Last season Snapchat went on to become the biggest new name at NY fashion week.

If you want to meet tech guys, you might catch them at Silicon Valley parties, which is how the Uber chief executive Travis Kalanick met his partner, Gabi Holzwarth, a violinist hired to play. Or they might be schmoozing clients downtown in a swanky Noe Valley club in San Francisco or a boring Union Square hotel in New York. In London you find them around Old Street, aka Silicon Roundabout, in bars, at hackathons, or start-up meet-ups. In the day they are coding at Google Campus or practising their pitching in a co-working space.

Some tech boys date the old-fashioned way: on Tinder. Airbnb founder Brian Chesky met his girlfriend of three years, Elissa Patel, through the app. When I interviewed Instagram co-founder Systrom he admitted that when he had been single he had signed up.

Dating agency Linx — presumably a play on operating system Linux — is dedicated to making Silicon Valley matches. Amy Andersen set it up in 2003 after moving to Palo Alto and being “flabbergasted” by the number of eligible men. She claims her clients are “extremely dynamic and successful individuals’’: tech founders, tech chief executives, financier founding partners of large institutions and “tons of entrepreneurs”.

Andersen says tech guys make “fabulous partners”. Romantic and chivalrous, they write love letters, plan dates, “even proposing on Snapchat!” If you want to marry a tech billionaire, she says, “you need to bring your A game.” Her clients look “for women who are equally, if not more, dynamic and interesting than he is!”

There are drawbacks to dating tech guys. Before Google buys your amore’s business, he will be living on *** Noodles waiting for the next round of funding — and workaholics are dull.

Kerr says Spiegel is “25, but he acts like he’s 50. He’s not out partying. He goes to work in Venice [Beach], he comes home. We don’t go out. We’d rather be at home and have dinner, go to bed early.” Which might suit Kerr, but is not my idea of a fun.

You had also better be prepared to share your life. When Priscilla Chan miscarried three times, Mark Zuckerberg wrote about it on Facebook, while Chesky used a romantic trip with his girlfriend to promote Airbnb - uploading a picture of her in bed, with a note saying “f* hotels”. Besides all of which is the notorious issue of Silicon Valley sexism.

It has a chief exec-bro culture that puts pick-up artist/comedian Dapper Laughs to shame. Ninety per cent of women working in the Valley say they have witnessed sexist behaviour, 60 per cent have experienced unwanted ****** advances at work, two thirds of them from their boss. Whitney Wolfe, a co-founder of Tinder, took Justin Mateen to court for ****** harassment. Her lawsuit against the company alleged that Mateen, her former partner, sent text messages calling her a “*****”.

Spiegel has tech bro form. He apologised after emails from his days at Stanford emerged: missives about stripper poles, getting black-out drunk, shooting lasers at “fat chicks”, and promising to “roll a blunt for whoever sees the most **** tonight (Sunday)”. After one fraternity Hawaiian luau party, he signed off emails “f*bitchesgetleid”.

No wonder some women are not inspired to become Twags. Especially when you could be a tech billionaire yourself. Would you not rather be Sheryl Sandberg, chief operating officer of Facebook, than married to the boss?Read more at:http://www.marieaustralia.com/evening-dresses | www.marieaustralia.com/black-formal-dresses

Keira Knightley
Ties her shoes
Too tightly
And we must not scoff
If her feet fall off.