Greening the red

Electric buses have been visible on Mumbai’s roads in the last few months. The plans seems to be to put 340 electric buses on the road by early next year. That is about 10% of the fleet. Quite a fraction of the new buses seem to have been deployed already. I haven’t been in one yet, but they are supposed to have 60 seats, and space for 30 standees (there’s another version with 25 seats). A friendly new feature is a mechanism to lift wheel chairs into the bus, or lower them to the road.

Yesterday my taxi was held up for a minute while this but backed into a parking bay on a narrow road. I clicked the photo you see here, and looked up the technical specifications. In normal use the engine uses about 150 KW from a Lithium battery which stores 186 KWh of energy. That rating should give nearly 100 hours of run. I suppose the reality is more restrictive, because according to the BEST (Brihan-Mumbai Electric Supply and Transport corporation) press handout, the batteries are supposed to last 200 Kms on city roads in a single charge. The bus is fully electric, from start to stop, and has no clutch or gear control. The company lists in-bus utilities like charging points for users and WiFi on the go, but the BEST press release does not mention them. I guess I will have to check these out when I ride the buses.

I was surprised to find that these buses have already run over 4 million Kilometers on city roads, in various cities. There are hybrid electric buses already running on intercity routes. These are the visible results of the government’s scheme, FAME, for Faster Adoption and Manufacturing of Electric vehicles in India, started in 2015. If these emission-free and (relatively) noise-free buses turn out to have a lifetime of 15 years, like the older buses on the roads, then it will be a rather nice and big change.

Counting the days

Finally, the tickets are booked. I’m looking forward to a trip through the Himalayas again. Wonderful views would be great, but no views, just fog, is also welcome.

There are very few things I want in life (only about a hundred and forty seven), and the pandemic has taught me to seek a balance between them.

Rally on Republic Day

There are several things that happen around now in most years: many classical music concerts, the Mumbai Marathon, and (my favourite spectator sport) the vintage car rally. Unfortunately none of them are happening this year. So here are some photos from a past rally, ten years ago.

Have a fun republic day.

PPE pollution

We’ve all been very happy with the decreased soot and dust in the air and the lower level of noise pollution. The anxiety of having to deal with the COVID-19 pandemic makes these positive changes great things to hold on to. Unfortunately, as life starts again, this will go back to normal. The immense economic disruption that the whole world has gone through will mean that little money will be left to improve soot emissions in the short term. And then there is one invisible bit of pollution which will spread even more. That is the disposable PPE. Already, for several years now, pollution from single use plastics was a major concern. Now we will begin to add more to it. Airports are producing a lot of this every day as air travel has opened up again; market places are full of it too. The Family took a photo of her hairdresser in a disposable kit. This is an indicator that there will be wider use of such things as the economy opens up again.

Fortunately, some people have taken notice. There is a very timely paper from a team of chemists in Dehra Dun who test a solution to this problem. They reduce this to a fuel which is similar to industrial diesel. The simple process was proven in other contexts, and is not new. Another nice thing about this process is that the plastics don’t have to be separated. One can take entire garbage bags full of the kits and use them as starters. So there is a problem, there is a solution. What is needed next is to take this out of the lab and into the world. That needs economic and political will.

A fun show

At one end of Wuhan’s Han Street entertainment area is the Han Show Theatre. Modeled after Chinese red lanterns, the architects Steven Chilton and Marc Fisher (who was the director of the opening ceremonies of the Beijing Olympics) created a theatre that made it difficult not to have my jaw drop. What looks at first sight like a grandiose stage swings away to create a deep swimming pool. The front seats draw back from the pool area. Behind the immense stage three screens descend to form a backdrop on which videos play.

This slideshow requires JavaScript.

I got to see the Han Show, crafted by the Belgian theatre director Franco Dragone. While watching the spectacular acrobatics and aquatics show I thought to myself that this was the Cirque du Soleil on a really grand Chinese scale. I was happy to find later that I was not mistaken; Dragone was one of the creators of the Cirque du Soleil. Given a 2.5 billion RMB investment from the Wanda group, the architects and directors created a ninety minute show that leaves you with a great big smile on your face.

At a late point in the show I realized that I did not have to take stills. So here is a video of a part of the show that was fun. Not as impressive as the forty meter high dive (one of the photos in the slide show above), but great fun.

Train to Nanjing

One of the things I like to do in China is to take a train, the high speed G train (高速动车组列车, Gāosù dòngchē, or simply Gāotie). I took one such from Wuhan to Nanjing and back. Amazingly, the train sustained a speed of 247 Kilometers an hour for a substantial portion of its 500 plus kilometer route. The result is that the two and a half hour run easily beats a car or a plane for its convenience. From the first time I took a Gao train, I’ve been impressed by its stability: a bottle of water set on a table in front of you barely has ripples on its surface.

In the early 90s, when China started developing its own high speed trains, the average speeds of Chinese trains were 48 Kilometers an hour; as a result cars and flights had begun to carry larger fractions of long-distance traffic. But now, with the fast trains, everything’s changed. There are no direct flights between Wuhan and Nanjing, for example. With over two thirds of the world’s fast trains, Gaotie is China’s contribution to green travel.

In keeping with this marvelous achievement, the new train stations are monumental (see the entrance to the Nanjing South station in the photo above). Since I planned my travel to maximize my time in Nanjing, I found it very convenient to find a marketplace inside the station where I could buy dinner before getting on to the train.

Sober cold stone

You enter the Hagia Sophia from the narthex on the west, so that the first thing you see when you step into the square naos is the immense apse right in front of you. It is difficult to tear your eyes away from it, but it is worthwhile later to come back to this place and look at what was behind you. The beautiful west gallery above you is fabulously decorated with mosaics and a carved stone railing between elegant pillars (featured photo). The gallery had collapsed in an earthquake in 989 CE, and the portion which was rebuilt has painted plaster instead of the mosaics of the rest of the interior. You can tell this easily by the fact that the paint is beginning to peel.

The details on the pillars are amazing. I brought my camera down to the pillars that hold up this curved gallery simply because it is there. Time and invaders have been kind to this part of the structure. The details are as razor sharp as they would have been 1500 years ago when they were freshly chiseled out. It is hard to remember that the use of regular geometric floral motifs was deliberate: it would be faster to do this repeatedly.

Above the Imperial Door in the middle of the western wall is this small stone inlay panel. I’m fairly certain that this must have symbolic meaning, but neither my audio guide, nor any references throw any light on it. I could remain ignorant for ever, or I could toss this question out to you (o gentle reader). What is the symbolism in this panel?

In the south eastern corner of the naos the light was much better. The carved capitals of the pillars were as breathtaking as the black, white, and red inlay work in the wall next to it. But all this was outshone by the mosaic above the pillar, with its large fields of gold. This is stone on fire, heady, breathtaking; quite the opposite of stone cold sober.

On another wall we came across panels of marble: Afyon marble, white with purple patches, alternating with Carian marble, red with white flakes. Between the panels ran a band of Tunisian marble with its dark veins running through reddish white. The light from the large windows lit up this wall and the gold tesserae of mosaic above it.

The cubicle that you can see in the photo above is the library of Sultan Mahmud I. We looked through the golden grille in the southern vestibule which separated it from the rest of the space. My audioguide did not warn me to spend time looking at the railing above it, which you can see in this photo. This railing is decorated with a repeating pattern of regular nonagons (nine-sided polygons). Constructing regular nonagons with compass and ruler is an ancient problem, and its solution presented in this railing was a statement about the mathematical prowess of the architect, Mimar Sinan. I must remember to take a close look at it the next time I visit this museum.

Let me end this post with a photo taken in the south gallery, one level above this. Again you see the wonderful carved capitals of the pillars similar to those in the featured photo. The complexity of the mosaic above the pillars is astounding for something made in the 6th century CE. Beyond it you can see part of the central dome, with the some of the forty windows which run around its base, and the forty ribs which support it. This was the main innovation of Isidore the Younger when the dome was re-erected in 563 CE, five years after the earthquake which destroyed the original dome.

Stress and buttress

I was trying to get a close look at the western turrets added to the Hagia Sophia in the 16th century CE by Mimar Sinan (featured photo) when I realized that I was looking at four buttresses to the church. I stepped back a little to photograph them in their entirety (below) and realized that they were actually flying buttresses. I’d thought that they were invented in the 12th century in France, so this surprised me.

Hagia Sophia is remarkably stable, given the frequency of earthquakes in Istanbul. Over 1500 years, the dome has had to be rebuilt only twice. A large part of this stability is due to the geometric design of the dome, with its supporting half domes built atop a central square section. However, recent studies found that the improperly cured bricks and mortar miraculously make the structure stronger than properly cured bricks of the 6th century would have. This is likely to be an accident of the hurried construction of the church, rather than deliberate materials science, especially since this technique was not used in any other Byzantine structure. Even with this fortunate accident, the pressure of the huge dome would have caused the structure to collapse if it were not for buttresses added over the years.

The four flying buttresses on the western facade, which you see in the photo above, are remarkable. They look like they are, at least in part, made of the same material as the rest of the western facade. This was rebuilt in 994 CE, within five years of its collapse during the earthquake of 989 CE. So I wondered whether the flying buttress was invented by the Byzantines before the French. The older view is stated clearly in this paper from 1935, “… we can at once discard any hypothesis which would date these buttresses to the ninth century, for the simple reason that flying buttresses were unknown before the twelfth century”. This paper buttresses this erroneous reasoning with an aesthetic judgement that these four are different from “ungainly masses” which were erected by Byzantine and Turkish architects, and so must have been made by French engineers who arrived here during the Venetian occupation.

The modern view is different. Flying buttresses have been discovered in buildings in Cyprus which were buried in the 8th century CE, well before its reinvention in France. So these buttresses which puzzled me could have been a Byzantine construction from the 10th century CE. In a structure as old as the Hagia Sophia, one seldom has a clear answer to questions of provenance unless there is contemporary documentation. For these four there is none, although the circumstantial evidence is that the buttresses are about a thousand years old. This raises the inverse question, could the egineering idea of flying buttresses, which began to be used from the 12th century in western Europe, have been carried there from Byzantium?

Three views of the Third Yangtze River Bridge

Last week I was in a meeting in Wuhan, a city that tourists overlook. This powerhouse city in central China was the origin of the successful Republican revolution which overthrew the last Qing emperor in 1911, and, in succeeding years, became the capital of the nation for brief periods. One of its sights is the Soviet-era bridge across the Yangtze, the first modern bridge to be built across the river. That was in 1957. Other bridges have come up since then. I find the third bridge very photogenic. The featured photo is a view at sunset, just as the lights came on.

Walking between two tall brutalist concrete blocks, I looked up to see the nearest tower of the three and a half kilometer long cable-stayed bridge, lit up by the afternoon’s sun on the day of the summer solstice. This was a lucky shot because it had threatened to rain all day, and the sun had just briefly come out as I walked out towards the bridge. This is not a very famous bridge, having been completed in 2000 during a period of intense construction. Its main span is 681 meters, which makes it only the 31st longest span among cable-stayed bridges today. Still, I liked the looks of it.

It passes right next to the Hilton. I crossed a road and walked out under the bridge where a little riverside promenade has been built up. This was a cheerful place with families walking around. A toddler inspected me carefully as I took this shot, teetering and nearly out of balance. His father smiled at me. In most other countries my bright red phone causes people to recoil a little. In China it does not draw a second glance. Red (红 = hóng) is a lucky colour, and very common. What a strange happenstance that the colour of the French revolution of 1789, found its way through the Paris Commune, and its adoption by the Communist movements of the world to this country where it is the traditional colour of joy and luck.

The biology of bridge-building

When you think of bridges you don’t usually think of biotechnology or gardening. But that is exactly what the Khasis traditionally did. First you have a gorge to be bridged, then you find two rubber trees facing each other across the gorge. Next you coax the roots towards each other, perhaps along poles or planks. Then, when the roots meet each other, you begin pleating them together and, by a process called pleaching, encourage them to fuse. That’s how the bridge that you see in the featured photo was built.

Once the platform is ready, layers of mud are laid down over it to make a easily traversed road. I suppose the weight that the roots can carry is a concern. On the day that we were there a couple of people were standing at each end of the bridge to do some traffic control, mainly to make sure that the platform was not overloaded.

If the general shape of the bridge looks familiar, it is because it is structurally a cable-stayed bridge. The framework of joined roots forms a platform which could sway in a monsoon storm. As you can see in the photo above, branches are brought
down to stay the platform. As an engineering design, Mumbai’s sea link is no different from this. Interestingly, it seems that the whole community which uses the bridge is trained to carry out repairs on it, so that a villager passing by can braid the roots a little and put up a truss to guide a branch.

This particular living root bridge was close to Mawlynnong village. There are many of these bridges scattered across the Khasi and Jaintia hills. I guess it takes time for the tree to grow, but it can’t be many years. I’ve seen other Ficus trees grows roots which touch ground within months. So I guess it might take no more than a decade to make a bridge. Ficus elastica, the rubber plant, is said to live for about 200 years in the wild. So, during its lifetime the bridge would get stronger. If the community plans well, then they can even begin to replace an old tree before it dies. It is said that one of the root bridges near Sohra (Cherrapunji) has lasted 500 years. This could be hearsay, since the earliest documentation of these structures was published in 1844 in the Journal of the Asiatic Society of Bengal. However, it is not unthinkable that this could happen, given that the technology is widely shared between tribes.

The banks of the river here were not very high. In winter the water reduces to a trickle. So I climbed down to the river bed to take a look at the interesting flat stones along the bed. Much of the clan had already gathered here. The pools and stones were nice and cool after the climb down to the river from the road. I was impatient to get back up. People were selling cut pineapples dipped in red chili powder on the track, and I needed some of that.