North Calcutta

Street Cooking

We get up early in the morning to meet Sunayana and Kenji from Calcutta Walks, at Shovabazar ((Best pronounced ‘Shobabajar’ – Bengali doesn’t actually have any v or z sounds, but they’re often used in transliteration of words and names out of deference to their Sanskrit or Persian origins)) Metro station ((I’ve written about my experiences on the Kolkata Metro, here, if you’re interested – and you can follow links from there to more writing about my trip…)) in North Calcutta ((for no very good reason I’m spelling Kolkata as Calcutta throughout this; both spellings and pronunciations are in widespread use by residents, and I tend to use the other, but our guides use the old-fashioned/English spelling in their name, and ‘North Calcutta’ is an English phrase – if I’m talking about Kolkata, should I call it Uttor Kolkata as well?)). They are to show us around some of the old houses and narrow streets of this part of the city. It’s uncomfortably early for me, but it’s worth it to be able to walk around in the mild heat of the morning, rather than the scorching sun of mid-day.

North Calcutta Courtyard

This is where the richer Bengalis mostly made their homes in the time of the Raj, and thanks to this it is one of the few parts of Calcutta with a visible history of secular Indian architecture, going back more than a century or so. From the street itself upwards, everything man-made here looks and feels more Indian than most of Calcutta, where nearly all the public buildings (temples aside) are obvious Colonial hangovers, and newer developments are so often so obviously modelled after their Western equivalents.

Portal

Here we see why Kolkata was known as the ‘City of Palaces’ – an unlikely number of spectacularly grand old palatial homes are clustered here, built by rajas and nawabs to show off their status and house their families for centuries to come. Their wide courtyards are surrounded by beautiful arches with expansive rooms beyond, and since we are there in the lead-up to Durga Puja, most of them also have particularly impressive shrines set up in them, each in the house style of the family that owns them. Although many of their proud residents are quite happy for us to pop in and look around in wonder, very few of them allow photography.

Old Kolkata Printing (1)

We briefly visit a very small press, printing packaging on letterpress machines older than independent India. Many such tiny industries exist here, where the old families often find themselves with more property than money, and rent out the odd room to make ends meet.

Our guides buy us some ludicrously cheap, very tasty and reasonably safe fried street food, served in disposable little bowls made of leaves, and take us to see traditional sweets being made. It is fascinating to watch these vast pans of curds and syrup being skilfully manipulated into tiny confectionery treats, but preferring to avoid dairy, I only allow myself a taste.

Another highlight is the maze of narrow, twisty streets of Shovabazar, where dacoits and resistance fighters alike could vanish as required. The sheer number of available alleyways would fox pursuers, and the tiny space between opposing walls would keep out any vehicles, and in many places it would make it easy for a competent climber to vanish in seconds. With sympathetic residents on your side you could melt away here like nothing, and never be found again.

Caustics

I have been fascinated by caustics for a long, long time. I still remember the first time I noticed them – a bright, ethereal form dancing in the shadow of my mother’s wine glass. I was entranced by the way the light moved when the wine swished in the glass, and disappointed when my usually all-knowing mother wasn’t able tell me anything much about them.

Many years later, a friend asked me if I happened to know anything about caustics; I had never heard of them, so she explained that she was talking about the shifting patterns of light made by rippling water, the curves of light you see at the bottom of mugs, and so on. Finally I had a name for these patterns that had enchanted me since my infancy; when I got home I looked up the word, wondering what these things might have to do with caustic soda or holocausts.

Most caustics are quite harmless, but if you have ever used a magnifying glass to focus the light of the sun into a tight point to make smoking holes in things, you have witnessed their potential destructive power; this is where they get their name. Archimedes is famously said to have used a giant parabolic mirror to set fire to Roman ships using reflected sunlight, during the siege of Syracuse in 212 BC. In modern times, the Olympic Torch is similarly lit by a large parabolic mirror focusing the sun’s rays on a single point.

Caustics can occur whenever light leaves a curved surface; most often that means it has been reflected or refracted. Refraction caustics, caused when light rays are bent by passing through something, tend to show less extreme distortion than reflection caustics, but often show subtle colour variations like light from a prism, because shorter wavelengths of light are refracted more than longer ones.

'city (dawn reflections) rooftop' courtesy of suchstuffEither kind of caustic can hugely amplify tiny imperfections or very subtle curvature into striking patterns, the effect increasing with distance from the surface. For example, very few windows are truly flat, and it is common to see cross-like shapes or mottles reflected on the walls opposite, when the sun is low in the sky.

caustics in motionStrictly speaking a caustic is the entire envelope of light which leaves a curved surface; the patterns of illumination we usually see are just the intersection of that three-dimensional structure with another surface. Something of the 3D nature of caustics comes out when the distance to the illuminated surface varies, with some features getting washed out with distance while others become ever more prominent. See this short video clip for an example; there’s a much longer film, with music, linked here.

We’d notice very quickly if they weren’t there – simulating realistic caustics is an important issue in computer graphics mainly for this reason, and an otherwise convincing scene will seem oddly flat and unreal if it is missing caustics that should be there. Mostly, though, caustics are one of those kinds of things which quietly make life that much more pretty while they just sit in the background, beneath our threshold of conscious attention – but which often reveal truly striking beauty when we pay them a bit of attention.

Additional photos courtesy of Reciprocity, SEngstrom and suchstuff; see more in the Caustics pool on Flickr. You might also like to play about with my interactive caustics-simulation animation, Zoobie.

Tea Tasting

On Tasting

Flavour perception is a deceptively complex thing. Human taste buds are capable of sensing salty, sweet, sour and bitter (the four classical elements of human taste) plus umami (the savoury taste of glutamates such as MSG, found in things like mushrooms, soy sauce and meat) and probably fat (the jury is still out on this one, but the evidence is strong). However, none of those play a central role in tasting something like most good tea or wine!

Most of the flavour of the most interesting drinks comes from their aromas. Our sense of smell is easily the most elaborate of all our senses – unlike the five or so basic tastes detected by our tongues, or the three basic colours detected by our eyes, our noses are capable of distinguishing thousands of different molecules.

Complicating matters further is the interaction between olfaction (the sense of smell) and gustation (the sense of taste provided by the taste buds); sometimes we won’t be aware of an aroma until we taste something with our tongues, and sometimes a particular taste becomes obvious only when we smell something associated with it. The two are bound up together so tightly that most of the time, people are not even aware that they are ‘tasting’ things with their noses, not just their tongues. For this reason it is always worthwhile to be conscious of the smell of fine teas, wines, whiskies and so on before tasting them, but also aware that the depths of their flavour cannot be judged until they reach the tongue and the palate.

There’s more: Add to the gustation and olfactory components the trigeminal sensations of pain and heat triggered by both physically hot and spicy hot food; the effects of texture, known in the business as ‘mouthfeel’; and astringency – the quality of tea, red wine and some fruits which makes us pucker our mouths, regardless of how they actually taste.

On Teas

So, to tea: What can we say about how tea tastes, and why? For a start, the overwhelming majority of true teas are at least a little bitter, and all are astringent to a greater or lesser extent. The tiny fragments of blended black tea used to make your basic tea bag for English tea are extremely bitter, and so astringent that the infusion is almost impossible to drink straight. Thankfully though, the molecules that give it these properties bind to the proteins in milk just as readily as they will to our tongues. They can also be more fully dissolved into the tea by adding lemon or some other mild acid – one of the few times when adding lemon makes something much less bitter. You will also notice that strong black tea clears and brightens almost immediately when lemon is stirred in, for exactly the same reason.

Lighter black teas like Darjeelings and Chinese black teas (Keemun, Yunnan and so on) tend to be much lesser bitter than their cousins, but this is largely because they are standardly brewed weaker. These teas have a depth of flavour coming from their subtle aromas, and many people feel that this goes to waste when they are made with milk, which has its own not-so-subtle smell. It might be argued, though, that a little milk is not offensive in a cup of the more robust light black teas, allowing for a stronger brew without totally overpowering the flavour.

Good green tea is usually not more than slightly bitter, as long as it is drunk while hot, and not brewed too strong. However, green tea bags are usually made with far too much tea, low-grade and broken up, and in my experience almost always make a bitter brew. Brewing temperature is absolutely crucial with green tea, which should never be made with boiling water; scalding the leaves that way not only removes much of their pleasant flavour, but gives them a new acrid flavour, which puts many people off the tea entirely. Many green teas have a flavour dominated by vegetative tones. This might be accompanied by a gentle smokiness, as in gunpowder tea and chun mee; rich, slightly flowery depths, as in pi lo chun (bi luo chun); or a sort of sea-sidey almost-fishiness in the case of most Japanese green teas, which sounds like it would be horrible but is actually oddly pleasant.

Oolong tea is tea which has been partially oxidised, placing it between green tea (which is plucked and dried quickly before the leaves can blacken) and black tea (in which the leaves are rolled or cut, and carefully oxidised over the course of several hours before drying). In general, it tends to have richer aromas than any other unflavoured tea, and most varieties are notably much less bitter than any black tea. There is enormous variety in the range of oolong flavours, and also extraordinary depth to them. Some are sweet, some flowery, some toasty, some autumnal, some have flavours which the English language is quite at a loss to describe. Good Chinese tea sets designed for oolong sometimes include separate ‘scent cups’, into which the tea is poured before it gets to the tiny drinking cup, just to give the tea drinker an opportunity to savour the aroma more deeply.

Like green teas, oolongs can generally be brewed several times, and each brew will often bring out different flavours from the last. Temperature is again important; though oolongs are not so thoroughly ruined by too-hot water, much of their taste will go to waste.

White tea is the lightest of all the true teas, made from young leaves plucked while they still have the baby-hairs on them and dried at once to preserve them in almost the same state they came off the bush. They have gentle flavours, never more than a tiny bit bitter when brewed correctly, often with a sweet aroma somewhat reminiscent of honey. Despite the softness of their flavours, there is a depth to them which should be lingered on. White teas must be brewed with water well below boiling point, and can be steeped repeatedly.

Pu-erhs, sometimes described as ‘post-fermented’, are a whole world of tea to themselves, despite being a relatively tiny niche market. Their musty aroma often borders on mouldy, which puts many people off, but they do have a pleasant, earthy richness to their taste which belies their smell. Pu-erh fans tend to be extremely enthusiastic about it, often to the puzzlement of the rest of the world. Pu-erh tastes like it must be good for you, and according to Chinese tradition and some scientific studies, it really is.

Some of the best-known of Chinese teas are flavoured, and derive most of their character not from the tea itself but from things added to it. Proper jasmine tea is flavoured by being left with drying jasmine flowers to absorb their flavour; lapsang souchong is smoked, traditionally over pine wood, to obtain its intense, tarry aroma; Earl Grey is scented with oil of bergamot, obtained from a particular kind of orange. Genmaicha, popular in Japan and Korea (where it is called hyun mi nok cha), is made of green tea with roasted rice, and it is the toasty flavour of the rice that dominates its taste.

Another toasty tea is hojicha, a rich brown tea made by roasting green tea. It has an unusually savoury taste, with a slightly nutty aroma; although it is not yet well-known in the West, it is generally extremely popular with those who have tried it. It is low in caffeine, and can be drunk hot or cold – for my money, it makes the most refreshing iced tea there is.

All photos are by the author except ‘Think in Pictures‘ by munded and ‘Pu-erh tea‘ by shop boy.
Links in the text are to further tea writing by the author.

The Cloudspotter’s Guide

The Cloud Appreciation Society was founded by Gavin Pretor-Pinney in 2004, to ‘fight blue-sky thinking’, with the motto: ‘Look up, marvel at the ephemeral beauty, and live life with your head in the clouds‘: Sound advice if I ever heard it. The Cloudspotter’s Guide is its first official publication, and the author’s first book.

Pretor-Pinney also designed the Guide, typeset it and put together the diagrams, and in every case he has done a beautiful job. This volume is gorgeously produced, with a delightful, atmospheric woodcut opening each chapter, plentiful photography throughout (mainly contributed by members of the Society) and the old iconic cloud symbol from the BBC’s weather forecasts serving as a vignette between each section. All in all, the design gives the book a dreamy, flighty air, in keeping with both the subject matter and the style of the prose.

The writing is fluid and un-self-consciously eloquent, rambling without ever getting tedious, educational without ever getting lecturey. The author skips amiably from topic to topic, interweaving personal and historical anecdotes, scientific observations and poetic ruminations on the beauty and vitality of the skies.

Each of the major classes of cloud has a chapter dedicated to it, always going into some depth about what characterises the clouds in question and talking a little about the meteorology of it, but often spending more time talking about other things – clouds in history and art, say, or various phenomena that come along with the clouds themselves (most of the Cirrostratus chapter is devoted to discussing ice haloes, for example; much of Nimbostratus is about rain from all sorts of different clouds).

The beginning of each of these chapters features a summary table for the clouds that are its nominal subject, giving a few illustrative photos, telling you where they form, in what species and varieties they appear, how to distinguish them from any superficially similar clouds, and so on.

The scientific details are substantial enough to satisfy the amateur meteorologist in me, but never so technical as to bog down the flow of the writing; where the author has had to simplify to make it comprehensible to the general reader, he is not afraid to say so, and the insatiably curious can always follow his pointers to more in-depth work.

Mammatus cloudsAfter the ten chapters for the main cloud groups, the last section of the book (‘not forgetting…‘) goes onto things which couldn’t quite be fitted in elsewhere. First, there is a chapter on The Other Clouds – accessory clouds such as the pileus (‘like a cloud haircut’) and pannus (‘dark shreds of condensation, which form like ghostly apparitions in the saturated air of rainfall’) which only appear alongside other clouds; supplementary features such as the incus (anvil) that often extends from the top of a Cumulonimbus cloud, or the breast-like mamma clouds that occasionally blob from the bottom of that; and the high, high clouds that form way above more common clouds, up in the mesosphere or the stratosphere – nacreous and noctilucent clouds respectively.

Chapter Twelve’s subject is contrails, the trails of condensation that form behind high-altitude aeroplanes.These streaks may provide an interesting glimpse into the process of cloud development, but they are also strongly implicated in climate change; it is largely thanks to them that the contribution of aeroplanes to the greenhouse effect is almost three times as large as it would be if CO2 was the only thing we needed to worry about. Much of the chapter is spent exploring the threat of global warming as it relates to aeroplane exhaust, with a substantial portion also given over to the history and science of cloud seeding – a technology which can be surprisingly effective in inducing rainfall (albeit only when the conditions are right), and which gets discussed oddly rarely considering the power of it.

In the final chapter, the author goes into journalist mode to recount in detail his mission to visit the Morning Glory, a spectacular and near-unique cloud formation in northern Australia, where rolls of cloud can be seen stretching from horizon to horizon as they make their way over the outback. Glider pilots come from all over the world to surf on its extraordinary, visibly roiling updrafts, and witness one of the world’s most awesome clouds. Despite the stylistic departure, the story provides a surprisingly elegant close to the book, as the author soars alongside a few of this planet’s most devoted cloud-lovers.

Skywatching

AweI recently finished reading The Cloudspotter’s Guide (see review), and have concluded that it is one of my all-time favourite books. I have made skywatching a hobby for as long as I can remember, but the book has raised my awareness of the skies above us to new heights. As it happens, this has coincided with some absolutely pheomenal skywatching weather in Edinburgh, warm seas and sunshine feeding vast Cumulus clouds, weather fronts dropping stunning Cirrus squirls from the heavens, fascinating layers on layers of different clouds.

I’ll return to the book later; for now I just wanted to share the results of just two day’s skywatching…

The first of those days found me sitting in Holyrood Park one fine, sunny-cloudy afternoon after work, with my camera and a copy of The Cloudspotter’s Guide, with nothing to do but read about, watch and record the sky. The weather was as good as perfect for it – strange ice clouds high above, brooding storm clouds just far enough away not to alarm, and enough sunshine to keep us warm and illuminate the early-autumnal haze with lovely crepuscular rays.

Cirrocumulus lacunosus undulatusWith the help of the Guide I was able to identify this unusual net-like formation with some confidence as a Cirrocumulus lacunosus undulatus – that is, a collection of high, icy cloudlets forming a layer punctuated by holes – lacunas, if you like. Granted, that doesn’t tell us much of any real use, but still, it’s always nice to be able to put a name to something that’s been puzzling you.

Puny HumansThe banks of Cumulus congestus dwarfed the Salisbury Crags, which in turn dwarfed the people climbing them. I knew that it would rain on us sooner or later, but I had time to capture a series of pictures to turn into a highly amateur time-lapse film, so that I could watch those beautiful convection cells in action later. There’s a small version of this here, but if your computer can take it I recommend the full 2-megabyte version. I could have saved myself a lot of work later if I’d had a tripod with me – and a timer would help – but I didn’t have anything fancy to hand, so I just balanced the camera on my knees and took a picture every few seconds for a couple of minutes – compressed here into a couple of seconds.

A few weeks later the skies around Edinburgh were dominated by vast, looming, ever-growing Cumulus congestus and Cumulonimbus: puffy, dramatic and often deceptively solid-looking rain clouds, pouring down their loads even as they burgeon with freshly condensed droplets, up-wellings of warm, moist air racing to refresh them before they rain themselves out. I was staggered to end up avoiding the rains entirely, though it can’t have been more than a mile or two away at any point in the afternoon.

That day’s convection clouds came accompanied by a smattering of Cirrus clouds streaming out of a subtle Cirrostratus, showing that the air was moist right up to the highest reaches of the troposphere – to the tropopause, where the weather stops. Their ice crystals refracted the sunlight in a stunning range of displays; I have been watching out for such things for years, but had never seen such a range of ice halo phenomena in one day.

There were striking sun dogs (also known as parhelia, or mock suns) – the most obvious of the halo phenomena, these appear more than once a week in northern Europe, but most people still fail to notice them. They are created by horizontally-aligned plate-like ice crystals; the sunlight passes through one side of these transparent hexagons and out of another, making a bright, coloured patch of sky 22° or so away from the sun – about the distance from thumb to little figure of an outstretched hand at arm’s length. The colours are not always obvious, but when they are you can see that the sun dog is reddish towards the sun, and bluish on the other side – sometimes with a long, not entirely un-doglike tail.

The exact same kind of ice crystals produce the circumzenith arc, a ‘sky smile’ in vivid rainbow colours, going part-way around the top of the sky, above the sun. As on that day, these are therefore likely to be seen at the same time – although they are not seen as often as sun dogs, partly because they only appear when the sun is quite low in the sky. In their case, the bright colours – which at their best can out-do any common-or-garden rainbow – are the result of light entering the top of the ice-plates and leaving through the sides.

Accompanying these, less spectacular but undeniably still pretty, I was unsurprised by the appearance of a 22° halo, the most common halo effect produced by Cirrostratus; these are made by columnar ice crystals, like tiny pencils, which are randomly oriented, and they appear almost one day in three. When these crystals have smooth, flat ends (which they rarely do) they can also produce a 46° halo, much fainter and much larger than their cousin. When the columnar crystals are roughly horizontal, they can also produce a tangent arc, somewhat resembling a giant dove made of pure light. If my judgement is on, I was privileged to see both that afternoon.

Salt Forms

The salt bin grinsThe salt bin opposite my flat provides me with a suprising amount of intrigue. Somewhere down the line, it filled up with water enough to become distended – or became distended enough to fill with water – so now it sits there and forever grins invitingly, like some kind of fat plastic crocodile.

It’s permanently full up with water now – intensely saline water, of course, which does some pretty interesting things when it’s stagnant… when someone dumped an old paperback in there, for example, it quickly became encrusted with those characteristically square salt crystals, like the ones you can buy at fancy delicatessens (‘fleur de sel‘)… although not so appetising.

Jagged salt spike layerLater, days of intense, steady sunshine led to some fascinatingly rich crystal formations around the borders of the salt bin, as an inch or two of the water evaporated.

Then, most recently, a combination of wear and tear with hot, hot sun and heavy rains have led the bin to start cracking at the sides, sweating its saline drips in waves to leave a story of the weather inscribed on its sides.

I suppose this would be a good place to write about the way crystals derive their shapes from the way their component molecules stack together, or about the echoes of geological forms in small-scale emergences like this.

…maybe some other time.

Oo…

Welcome to Fergus Ray Murray‘s new blog.

Why ‘Oolong‘?

  • Well, what with this being Teh Internets and all, I thought I had better come up with some kind of a pseudonym. I took the name of my favourite tea because I liked the sound of it, I wrote a song about it once, and it was also the name of the hero of quite a cool computer game I remembered from my youth.
    I only discovered later that I shared the name with the Internet’s most famous bunny, and the Pigsy character out of Dragonball. Such is life.

Why ‘Oo‘?

  • Oo is an interjection which can express glad surprise, or a moment of pleasure. I like that, and I thought I might enjoy keeping a log of things that make me go ‘oo’.

…Why ‘long’?

  • Call me a preposterous optimist, or – if you prefer – a gloom-mongering Lethargian – but I think there’s a fair chance I’ve got another fifty years ahead of me on this planet. Life is far too long to live without routinely taking pleasure in day-to-day things of beauty and wonder.

Have a cup of tea?

Some oolong tea