Dr Administrator

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Jun 03 2021

Book review: Guitar Pedals by Rob Thorpe

guitar_pedalsAnother brief sojourn with a guitar related book, this time Guitar Pedals by Rob Thorpe. It has the lengthy subtitle "Discover How to Use Pedals and Chain Effects to Get The Ultimate Guitar Tone", and the front cover continues with a range of other promises as to content. This isn’t intended as a criticism, it just struck me as an usual stylistic effect.

For those not familiar with electric guitars, an guitar effect pedal is a little box of electronics, around the size of a cigarette packet but rather thicker, with a socket on one side to take input from a lead from your guitar and a socket on the other side to send the modified signal out to your amplifier. On the top face of the pedal is a switch to turn the effect on and off, and one or more knobs to configure it. Guitar pedals are usually grouped together on a pedalboard which will hold up to 10 or so of them, chaining their effects together. They introduce effects such as distortion, reverb, delay and so forth.

If you watch videos of live music you’ll most likely notice the guitarist and bass player with a pedalboard on the floor at their feet, occasionally poking it with a foot to change the sound of their guitar.

Guitar pedals are a cheap and easy way of changing the way your guitar, I have a couple of more expensive Boss pedals which cost about £100 and a couple of Donner pedals which were under £40.

Guitar Pedals runs through chapters describing a bunch of distinct effects, talking first about the background of the effect before going through some short examples of the effect in different contexts with different configurations (these appear as written guitar tabs, and accompanying downloadable audio files), and finishing with some examples in real music.

Since reading "The Birth of Loud" by Ian S. Port it struck me that much of the development of the electric guitar and its ecosystem has been the story of electrical equipment abused. Particularly so with distortion /overdrive pedals described in the first chapter – the original distortion pedal made by Gibson in 1962 (the Maestro FZ-1) attempted to replicate the effect Link Wray achieved in Rumble by stabbing his speakers with a screwdriver! Jimi Hendrix was a fan of the Arbiter Fuzz Face but quality control was so poor he would buy a bunch of them and pick the best (or even get his guitar tech to cobble together a pedal from the parts of multiple examples). Purple Haze is an example of Fuzz Face in action. Overdrive is what you get when you turn the volume of your amplifier right up – pedals can achieve the same effect without making a really loud noise.

Next up is a chapter on delay – essentially an echo effect which was originally implemented on tape. I’ve always thought of delay effects and reverb being related with reverb the more important of the two. Reverb and compressor effects each get their own chapter but Thorpe sees them as more production effects than pedal effects per se. Tracks like Beautiful Day by U2, King of Zion Dub by King Tubby and Country Boy by Albert Lee use delay.

The chapter on modulation effects covers phasor and flanger effects, where part of the signal is phase shifted and mixed with the original signal. Shine on you crazy diamonds by Pink Floyd is an example of a phaser in use, and Barracuda by Heart uses a flanger. Also included are chorus effects (where part of the signal is delayed) and tremolo (where the volume is modulated). The first chorus pedal, the Roland CE-1 started life in Roland’s Jazz-Chorus 120 Amplifier. A background in physics is quite handy here, vibrations and waves are at the heart of any physics degree, as are operational amplifiers – pedal effects are these things in action! Come as you are by Nirvana is a good example of the chorus effect, and How soon is now by The Smiths demonstrates the tremolo effect (for this performance the tremolo effect comes from the amplifier rather than a pedal).

My wah pedal is my favourite, and it gets a chapter largely of its own. Think Voodoo Child by Jimi Hendrix (watch his left foot at the start of this video) or the theme from Shaft by Isaac Hayes. A wah pedal is an adjustable band pass filter, in the same why that the tone knob on any manner of audio equipment is an adjustable low-pass filter. The wah pedal is unusual in that you adjust it during play – the position of the pedal controls where the band pass sits, other pedals have their configuration set before hand and are simply switched on and off. All I can say is it’s great fun to play with!

Next up are octave pedals and other pitch shifters and harmonisers, I’d assumed the point of an octave pedal (which plays a note one octave above or below the note you are playing) was to emulate a bass guitar, but it seems not.Jimi Hendrix’s Octavia pedal added a tone an octave above what he was playing, on tracks like Fire and Purple Haze. Jack White of The White Stripes uses octave effects to add notes both an octave above and below the played note to give a "thicker" tone – try tracks like Ball and a biscuit and Blue orchid.

Originally effect pedals contained simple analog electronic circuits (or even liquids) which did one job, now with digital processing a single pedal can emulate many different effects. I must admit I find multi-effects pedals a bit overwhelming – it’s no fun trying to navigate 50 or so effects, and their configuration on a one inch display with a couple of buttons.

The book finishes with a chapter on ordering of guitar pedals, and how this can change the sound made and finally there are some interviews with professional guitarists, and how they arrange their pedals. A point that both Thorpe and one of his interviewees makes is that tone, the sound of the guitar, depends a lot on the player and how they play. Chasing after a tone by buying the same pedals as your heroes is a losing game.

Guitar Pedals is a short book, it doesn’t have the high production values of the Rikky Rooksby but it carries much of the style – embedding the example riffs in the chapters works really well for this book. Online guitar courses tend not to cover effects pedals, this book fills the gap pretty well.

May 30 2021

Book review: The Goddess & The Bull by Michael Balter

the_goddess_and_the_bullI like to vary my reading, so from my previous review on guitar riffs we go to Neolithic archaeology, specifically the archaeology of Çatalhöyük in The Goddess and The Bull by Michael Balter which carries the subtitle "Çatalhöyük – An Archaeological Journey to the Dawn of Civilization". Çatalhöyük featured in a recent TV programme "Raiders of the Lost Past with Janina Ramirez" which I recommend if it is still available – this is what prompted me to get this book.

Çatalhöyük, in Turkey, is a prehistoric township which was active between 7500BC and 6200BC, it reached a peak size of some 5000 residence and as such it notable for being one of the largest of the early Neolithic settlements.

The Goddess intertwines several themes, it provides some biographical detail of the key archaeologists involved in the dig, it talks a bit about the evolution of archaeological methodology, and it talks about what was found at Çatalhöyük and the wider human activity in the Neolithic period. This is laid out in chapters that proceed chronologically with each chapter mixing elements of biography, methodology and the Neolithic period.

Any story of Çatalhöyük starts with James Mellaart, the first archaeologist to dig the site in the early 1960s. It’s fair to say he was a bit of a character. When he arrived in Turkey in the 1950s the Neolithic remnants were little known and he discovered hundreds of sites in his tour, on foot, of the area. These were largely in the form of "tells", large mounds built of successive layers of settlement made one on top of another. Çatalhöyük stood out because it was large, and it was early Neolithic from top to bottom. Many of the tells were occupied over very long periods of time so the earliest archaeology was obliterated by the later.

After digs at Çatalhöyük between 1961 and 1965, Mellaart was banished by the Turkish authorities following accusations of facilitating the sale of archaeological artefacts. His case was not help by the "Dorak Affair" in 1958 in which a mysterious woman showed him a range of artefacts from the Neolithic which he dutiful wrote up in various articles – these artefacts never saw the light of a museum and the Turkish authorities suspected Mellaart in their disappearance. The mysterious woman has never been found. Over the rest of his life Mellaart continued to publish on Çatalhöyük, later articles becoming somewhat fanciful.

I found it striking how much of the archaeological work done in the Middle East was done by British, American and other Western European archaeologists, often with their own institutes in-country. It feels like a water-down version of the bad old days of the 19th century where Europeans pillaged the countries of the ancient world for artefacts, although it is clear these 20th century ventures were much more under the control of the "home" countries.

Also relating to politics, the book highlights how much modern archaeology is funded as rescue work, during the construction of roads and railways in the UK, and frequently dams and hydro-electric schemes in the Middle East. In the nineties phase of digging at Çatalhöyük, Ian Hodder, the director of the work, spent a lot of time fundraising from both public and commercial sources.

From a methodological point of view, Mellaart’s first archaeological digs were based on the vertical stratigraphic approach borrowed from geologists which had been made popular in the forties and fifties by Kenyon and Wheeler. Here layers of a site are stripped back successively to establish a chronology, aiming for depth rather than breadth. This replaced the 19th century approach of broad area excavation where discovering the horizontal extents of a site was the priority, as was the discovery of "treasure", I suspect. Following Mellaart’s excavation the "New Archaeology" arose which became the "Processual" movement in which the emphasis was on highly detailed digging and analysis with a view to testing hypothesis. Earlier schemes being more interested in cultural artefacts. In a nutshell, the processual view saw different forms of stone axes representing different uses, whilst the previous view saw different axes as representing different cultures.

Ian Hodder represented a further evolution in methodology, post-processualism which included the intensive specialist sampling of the processualists but added more context from sociology and anthropology, and even the subjective feelings of the archaeologists as they worked. Pierre Bourdieu, a French sociologist and a bête noire in our household, is mentioned! Hodder took over the excavation of Çatalhöyük in the earlier nineties, and continued through to the completion of this book in 2006, and beyond until 2017 when digging seems to have stopped at Çatalhöyük.

The core question around the Neolithic era was what made Palaeolithic hunter-gatherers settle and take up farming, and how did they do this. There is some evidence that settling, living in permanent villages occurred some time before farming started. But why did farming start? Why did settling start?

There isn’t really a conclusive answer to this. Çatalhöyük, as a substantial Neolithic settlement, is pre-dated by a short spell by sites such as Jericho. It is comprised on many relatively small dwellings with common features: evidence of a ladder and an oven on the south wall, indicating access from the roof, numerous human burials under the floors. There is no evidence of specialist or communal buildings or a social hierarchy. The walls of the buildings were decorated, sometimes with bulls’ skulls or vulture heads inside them. It seems that buildings were ritually burnt at the end of their lives, typically after one hundred or so years of occupation. The people ate cultivated crops, and domesticated sheep and goats and some wild cattle, more of the wild cattle during what appear to have been ceremonial meals.

One theme from the sixties epoch of excavation that didn’t make it through to the nineties was the idea of Goddess worship, in the sixties there was some enthusiasm for the idea that Çatalhöyük represented a matriarchal society which worshipped a goddess. This idea does not seem strongly supported by the archaeology, although there are a number of "goddess" statues discovered they are all small and not found in particularly salubrious situations. There is more evidence for the idea that the bull was venerated – I wonder about the links between this and the position of cows as sacred animals in Hinduism, and also its role as a pictogram that evolved into the letter "a".

I really enjoyed The Goddess and The Bull, having approached it somewhat sceptically because it was not the recommended book by experts (James Mellaart: the journey to Çatalhöyük by Alan Mellaart) and it wasn’t clear whether it was an intensely academic volume. The biographical material of the archaeologists is sometimes a little grating but it makes the book more readable. I felt I learnt a lot about archaeology and the Neolithic. There’s a website www.catalhoyuk.com, where you can see the latest developments – including annual reports up to 2017.

May 09 2021

Book review: Riffs: How to Create and Play Great Guitar Riffs by Rikky Rooksby

riffsAnother guitar book in this review, I previously read How to write songs on Guitar by Rikky Rooksby, this book Riffs: How to Create and Play Great Guitar Riffs is by the same author.

A riff is a short musical phrase which is repeated throughout a track, it is common on guitar in rock music. It’s pretty easy to identify a riff in a rock song – which bit of "Smoke on the water" by Deep Purple do you think of when I mention it? "Back in black" by AC/DC? "Money" by Pink Floyd? That’s the riff. Later in the book Rooksby tells us that a riff can be as little as a bar long and 4 bars at an absolute maximum but it can be reinforced by repetition and variation. It’s surprising how few notes are required for a riff – two or three are sufficient at a push, five or six are plenty.

Riffs (the book) is structured into 6 sections, the first three sections cover riffs built on intervals, scales and chords respectively – there are roughly ten types of riff in each section. Section four covers playing and recording riffs, beyond the bare notes in the riff. Section five is a masterclass with John Paul Jones, of Led Zeppelin. The book finishes with a section which provides notes on the tracks on the accompanying CD which are illustrations of all the different types of riff with a few extras.

The first three sections running through the different types of riff features examples from "real" music to illustrate (and usually several examples per riff type). I really like these examples to refer to in discussions of music, I’m not at the point where I can read Rooksby’s commentary and understand what he means but the examples help make sense of the words. I found myself sitting with Spotify beside me as I read playing examples as they were mentioned.

It becomes clear looking at the examples which types of riff are the important ones – they feature the most well-known examples. For example, the mixolydian scale riffs include "I can’t get no satisfaction" by the Rolling Stones, and the chord version of this scale include "Louie Louie" by The Kingsmen and "Won’t get fooled again" by the Rolling Stones.

Rooksby comments that it isn’t entirely clear what is a chord progression and what is a chord riff – he differentiates in terms of speed and distinctive rhythm – riffs are faster.

Guitar tabs are not provided for the examples, I suspect this is largely for copyright reasons. The book contains references to several hundred tracks – I don’t like to think about the amount effort required to collect permission for all of the guitar tabs for the key riffs!

The techniques section talks a bit about the process of composition – recommending a drum track to assist the process. One of the key insights in the book is how key the rhythm is to a recognisable riff. He also talks in this section about how riffs are arranged both in terms of what the bass and drums are doing with the riff and also how the riff is created potentially with multiple guitars configured differently to "thicken" the sound.

I’m ambivalent about masterclass with John Paul Jones, it read like a high level technical discussion which went over my head but it was interesting to see where riffs come from "from the horses mouth".

The accompanying CD contains 56 tracks, almost all under a minute long and most of much less than that. The first 16 tracks fit in with a more tutorial introduction. The core 30 tracks illustrate the types of riff introduced in sections 1 to 3. Each track has the riff in standard musical notation and guitar tab format. The tracks feature the riff with an accompanying drum and rhythm (chord progression) track. I really liked this section, it helped clarify what each of the riff types sounded like and how they were constructed. It was also rather nice to be able to follow along matching up the music to the tabs for short musical phrases.

Experienced musicians make much of the importance of ear training, normally bemoaning the fact they did not do more when they were learning. I think they forget how hard it is, ear training is a combination of listening and knowing what is likely to come next on the basis of musical theory (or a lot of experience). If you don’t have that implicit knowledge, ear training is really hard. This book is handy in providing musical context.

In common with How to write songs on Guitar, I really liked this book. Rooksby’s writing style is good, there is some music theory but what makes it great is putting that theory into context. My next task is to go through the riffs recorded on the CD with my guitar and the book and see if I can recreate them.

Apr 27 2021

Book review: Why I’m no longer talking to white people about race by Reni Eddo-Lodge

eddo_lodgeI recently joined the BLAC Liberal Democrats, spurred on by the Black Lives Matter protests last summer, and my varied reading. This book: Why I’m no longer talking to white people about race by Reni Eddo-Lodge seemed appropriate as a next read, it is about the politics of race in the UK. It follows on from reading David Olusoga’s Black and British and Superior: the return of race science by Angela Saini and also Hidden Figures by Margot Lee Shetterly which is a about black women working as analysts in the early American space programme.

To cut to the chase, the reason Eddo-Lodge is "no longer talking to white people about" race is that they get upset and angry, and this is turned on her. In practice, this book has had the effect of Eddo-Lodge talking to people about race more often.

There is an asymmetry in discussions of race between white people and black people in the UK, the white people hold the positions of power, the high ground. If they lose, they just lose a little debating game on the day, but for black people if they lose it reinforces the age old "go home" narrative, it questions their right to remain, there value as people.

One of the ideas that struck most from this book was that racism was prejudice plus power, I don’t think this is a novel formulation it is simply something I’ve never come across as an idea.

Why I’m no longer talking… is divided into seven chapters entitled Histories, The System, What is White Privilege?, Fear of A Black Planet, The Feminism Question, Race and Class, and There’s no Justice, Just Us.

It starts with a brief history of black people in Britain, starting after the First World War. This has been in the news recently – Commonwealth soldiers from Africa, the Caribbean and India were not commemorated in the same way as white soldiers for essentially racist reasons. The 1948 British Nationality Act enshrined in law that the citizens of the Commonwealth could claim citizenship in Britain. Black citizens in the Caribbean and Africa saw Britain as their Mother Country, as did their white counterparts in Australia, Canada and New Zealand. Britain did not see them in the same why, and ultimately the 1962 Commonwealth Immigrants Act re-labelled the citizens of the Commonwealth "immigrants" and restricted their access to Britain.  

The chapter "The System" starts with the racist murder of Stephen Lawrence and follows the 20 year story of how at least some of his murderers were brought to justice, largely through the persistence of the Lawrence family. On the way the MacPherson identified the Metropolitan Police as institutionally racist. In 1982 John Fernandes, a black sociology lecturer, solicited anonymous essays on race from students at Hendon Police College as part of an exercise to set up a "multi-culturalism" course. It is fair to say that some of the essays revealed some very racist views. The College was unwilling to offer an anti-racism course, they wanted multiculturalism. They were so upset at Fernandes’ proposal that they demanded he returned the essays on the grounds that they were written on police paper. Those 1982 cadets were 10 years older than me, they’d be 60 now probably approaching retirement some from senior positions. Would you like to bet whether they became less racist over that career? That racism did not inform their policing? That they didn’t influence subsequent generations of police cadets?

Eddo-Lodge prefers to talk about structural racism which is a bigger picture view that is not limited to individual bodies.

It is not difficult to find evidence of structural racism in all areas of life, in the stop and search statistics of the police, in the pay gap for middle class black workers, in maternal mortality in childbirth, in the discipling of black children in schools. I think particularly of the press and the differential treatment of Megan Markle and the Duchess of Cambridge, Diane Abbott and Boris Johnson, of Naga Munchetty and Andrew Neil, Donald Trump and Barack Obama. You can tie yourself in knots trying to explain these differences by other means but simple racial prejudice is a much simpler explanation. The Home Office is very clearly racist (what do you think the "Hostile environment" and vans saying "Go Home" are?). More disturbingly I think black teachers and black doctors experience more racism from some of their colleagues than we care to admit (let alone their patients and students). I suspect that complaints procedures are stacked against them. Complaints procedures are designed by middle-aged white men like me whose overwhelming concern about a complaints procedure is that it should protect middle-aged white men from "false accusations". 

White privilege is a term coined by Theodore Allen, a US trade unionist, in 1968. In many areas white people have an advantage simply by being white, their CVs are not rejected because their names or addresses indicate their colour. He astutely pointed that the working man would be unwilling to give up their white privilege. Let’s face it, all of us will feel we have struggled to get where we are, and it takes a long time to realise that some of those wins were simply because we were white and male. I found this easiest to understand when pushing my son’s pram around Chester, no longer was the environment built for me, the steps up onto the Rows became a serious obstacle, the narrow aisles of shops a tricky maze. The same applies with gender, I will happily run along the canal towpath by myself at any hour of the day, not so my wife who sees a risk from men in that. The women at work will talk to each other about which men not to enter a lift alone with. And so with race.

In his infamous 1968 speech Enoch Powell talked about the "black man holding whip hand over the white", this has been a recurring theme from the far right of a black polity holding power over the white. An inversion of the current status. It has been a recurring theme echoed by the National Front, EDL, the Vote Leave campaign ("we want our country back"). Eddo-Lodge spoke to Nick Griffith who talked to her about a "white genocide". Where does this fear come from? To a degree it is manufactured, white British people don’t wander around fearing the day a black majority will hold them as slaves. Perhaps it says more about the accusers and how they exercise power.

Eddo-Lodge suggests that admitting racism in the past is admitting defeat and that is why white people find it hard, as a white person I think there is an element of this but also admitting past racism implies that "compensation" may be due and as a white person that I think is what I "fear".

For me the most uncomfortable chapter was "The Feminism question". Essentially pointing that a lot of feminism is white feminism and pointing this out is seen as troublesome. It is uncomfortable for me because it begs the question: which under-privileged group do I back? I think the answer to this is that, as a white male, the correct thing to do is keep well out of it!

Britain is a class-ridden society, class is often a cultural identity – many people in managerial roles claim to be working class. The language around class is a throwback to a period long ago, the new working class are found in call centres and restaurants, not in factories or mines. If we think about class in terms of poverty then black and Asian groups are much more likely to be found in lower income groups. The image of the working class should be a black woman pushing a pram, not a white man in a flat cap.

But there is a new game in town, it is now seen as entirely acceptable for politicians to talk about helping the "white working class" – language that came out of the British National Party and the English Defence League but is now mainstream. This seems to imply that our efforts helping the black working class have been entirely successful and that the white working class are now "left behind" and need special support. In truth black, Pakistani and Bangladeshi working class remain more disadvantaged.

The final chapter talks about solutions, and is quite clear on what white people can do to help: support financially and administratively those black people taking the lead on racism, intervene in by-stander situations, speak up in places where there are only white people and talk to white people about race. It is easy enough for me to see the relevance of this book in my work (my work touches on face recognition and artificial intelligence both of which have turned out to be structural racist and sexist). To these things I would add that I’ve started following a wide range of black scientists on Twitter simply so that black people are no longer the stereotypes I see on the mainstream media, they are people like me.

The chapter title is a quote from Terry Pratchett, and to me it represents a moment of connection and common interest with an author who, on the face of it, is very different from me – I’m a big fan of Terry Pratchett too.

Eddo-Lodge asks what it is in the white psyche that makes race such an issue, in my view this is a combination of things. There is a quite universal human instinct to be suspicious of outsiders – I’ve seen this in Dorset where "people from London" are viewed with suspicion (although I now wonder whether their are racist overtones to this) and similarly in Austria about "people from the next village". Black people are very easy to see as outsiders. Added to this is a longstanding history of slavery and then colonialism where it became politically important to cast black people as firstly not even fully human under slavery, and under colonialism as not fit to run their own countries. These prejudices cast long shadows, independence has come to Britain’s former colonies in the lifetime of my parents, and not that long before I was born. The political world I grew up in was shaped by colonialism, and the racism that went with it.

I rarely make a judgement as to whether any books I read or "right" or "wrong". Why I’m no longer talking… is right in the sense that is the genuine record of Eddo-Lodge’s thoughts but it is also right in pointing out that the UK is riddled with structural racism and pointing this out makes white people upset. I found the book contained useful new ideas for someone like myself who is on a bit of a journey with regard to racism.

Apr 19 2021

Book review: Eye of the Beholder by Laura J. Snyder

A return to more traditional fare with snyderEye of the Beholder by Laura J. Snyder. This is a collective biography of Johannes Vermeer and Antonie van Leeuwenhoek who were both born in Delft in 1632. Vermeer, a painter, lived for 43 years and Leeuwenhoek most famous as a microscopist lived for 91 years. Alongside the stories of their lives, Snyder also talks about the events in Delft, and the wider Netherlands, and the evolving understanding of optical phenomena that is relevant to both painting and microscopy.

A theme of the book is the idea that Vermeer and Leeuwenhoek knew each other, and possibly knew each other quite well – with their expertise feeding in to each other. This is a link that Snyder has discovered, and is somewhat circumstantial since there is no direct evidence of correspondence between the two men. The main evidence for the assertion is that Leeuwenhoek acted as executor to Vermeer’s estate, some have seen this as no particular evidence since Leeuwenhoek was a public official who might be expected to take on this role. But he only did this for four people, three of whom had known personal links. The other piece of evidence is that they lived within a few hundred yards of each other in a relatively small city and shared common interests in optical phenomena so very likely knew each other, they both knew Constantijn Huygens. In some ways the existence of a personal link is not important, rather the drawing together of technologies of camera obscura and microscopes as new ways to see and understand the world.

I note that as someone who has worked both as a microscopist and in photorealistic computer graphics this book is particularly close to my interests, and strikes a chord with me. One of the challenges of microscopy is understanding what on earth you are seeing, and photorealistic computer graphics brings in to sharp focus the mechanisms by which an image is formed. Even now, three hundred years after Vermeer and Leeuwenhoek, specialists in these fields will have undergone a personal journey of discovery where they sought out the thing they were looking for down the eyepiece of a microscope (possibly spending more time than they’d admit focused on the top surface of the coverslip rather than the sample). In photorealistic computer graphics rendering forgetting to include a light in their model and pointed the virtual camera in the wrong direction, leading to a completely black image are not uncommon beginners mistakes.

In the 17th century the Netherlands was a hotbed of scientific discovery, trade and art – the so-called Golden Age which had started in 1588 and came to an end in 1672 with the Franco-Dutch War. Despite much scientific work, the Netherlands were not to have a scientific society like the the Royal Society until the 18th century. Private art was commonplace in 17th century Netherlands, Snyder associates this with religious sensibilities – as a protestant nation the Dutch did not favour extravagant public, religious art but compensated with art in their own homes. On average each Delft household had two paintings. Also relevant to the story is the fact that the Dutch had only recently started adopting surnames in the 17th century, and it seems in the beginning they were often chosen thoughtfully which is alien to the modern mind for whom surnames are generally a given.

In Delft the biggest event of the book is the "Delft Thunderclap" in 1654, an explosion at a gunpowder store that killed over a hundred people and injured thousands more.

The camera obscura is the focus of the artist side of the story, it had been invented some time around the 13th century, and it was to join other optical aids for artists. A camera obscura is basically a box with a hole in it (originally room sized), where an image of what lies outside the box is projected onto a wall. Hyperrealism though the use of the camera obscura was something of a passing fad, Da Vinci had been scornful of the use of such aids, and there usage was something of a trade secret for artists. By the 17th century the camera obscura had evolved from a simple room with light entering through a hole to a system, possibly even a portable box featuring mirrors and lenses. The camera obscura allowed the artist to capture the geometry of a scene by copying the projected image (indeed camera obscura were also used by surveyors). What’s more by separating the image from the scene it served as a tool to better understand how light interacted with materials. Vermeer’s work shows signs of his use of the camera obscura from the late 1650s.

This is not to diminish the skill of a painter, it struck me that Vermeer’s style had elements in common with the much later Impressionists with subtle uses of colour and line being used to give the impression of a scene rather than painting and exact replica to the canvas.

Vermeer was to die in 1675 at the age of only 43, 1672 "Rampjaar" had left him close to destitute as the art market collapsed, and he had 11 children to provide for. He left behind only 45 paintings from his 20 year career.

The microscope is the focus of Leeuwenhoek’s side of the story, the microscope had been invented in the early part of the 17th century but was not much used until much later in the century with Robert Hooke’s magnificent book Micrographia showing what it could achieve. Leeuwenhoek’s microscopes are quite different from those we use today, they are simple spherical lenses mounted in metal plates smaller than playing cards. Leeuwenhoek’s skill was persistent and careful observation over a period of 40 or so years, reported to the Royal Society in London in over 300 letters. He discovered microbes, red corpuscles in blood, as well as the wriggling tails of sperm amongst much else. He studied the inner workings of things rather than just the surface appearance, as Robert Hooke had done. His preparation of samples equals those prepared today. I recall that Leeuwenhoek was long ignored in the history of microscopy because his work was so much in advance of anything for years after his death and he kept his methods secret, although Snyder makes no mention of this so perhaps I mis-remember.

I really liked this combination of biography, national history and history of ideas. Snyder’s style is warm and clear, I also enjoyed her earlier "The Philosophical Breakfast Club".