The Dawlish Diversion

The recent problems with the seawall at Dawlish has left much of Devon and the entirety of Cornwall cut off from the rest of the rail network. This is problematic, but as I said in an earlier post, it is far from the first time it has happened. This week, National Rail released a document that shows some of the damage done by the storms, and the work being done to fix it. The last page includes a low-resolution map showing potential long-term diversionary routes that are being looked at. These include two potential routes (C1 and C3) that have a long history.

Because of the problems with the line, in the 1930s the GWR proposed a couple of alternative routes that would bypass the troublesome coastal route. Unfortunately there is a very big hill called Holcombe Moor in the way, and therefore any line was going to be very heavily engineered.

The first alternative route headed south from Exminster, bypassing to the west of Kenton before heading more or less directly south to Dawlish, where it headed to the west of the town before curving southwestwards under Teignmouth to rejoin the existing line to the southwest of Bishopsteignton. This would require about eleven miles of new double-track railway, and is depicted by the red line below.

The alternative replaced the northern half of that route, leaving the existing line to the north of Dawlish Warren and heading under the town before rejoining the route mentioned above in Dawlish. This route would require seven miles of new double-track railway, but would be subject to tidal conditions along the Exe estuary, and would probably be slower. It is depicted by the light-blue line below.

The GWR got the former plan through parliament, and actually started construction when war interrupted in 1939. Given recent events, many people are thinking of building another diversion line, so I thought I'd take a look at what the GWR proposed.

Thanks to David Brown on the Railform Blog, I've found a map of the proposed routes. This is not the whole story as there were other proposals, but it's interesting nonetheless. I have transcribed the routes onto a modern OS map:

As can be seen, Dawlish Warren and Dawlish will still be able to be served by trains, albeit the latter a kilometre from the seafront. Teignmouth, however, will be more difficult, as the line passes behind the town in a very deep tunnel.

To my surprise, there does not appear to have been a massive amount of development over the last seventy-five years that would stop either of these lines being built. True, there would be some demolition, but not as much as I feared.

Either of these routes would be fast and weather-proof, and would serve the south of Devon with similar service patterns to those that already exist. The line could also be electrified. The downsides that I can see are cost, and the problem of giving Teignmouth a station.

If more information comes out on the C2 alternative in the Network Rail document (which seems to leave from north of Starcross, midway between the two routes above), then I shall do another post.

For another alternative proposal, see http://www.townend.me/files/southdevon.pdf

The bridge at Bayonne

As we ramp up to commemorate the start of one vast European war a century ago, it is easy to forget that another vast European war drew to a close two centuries ago. 1814 saw the end of the Peninsular War, which had seen various European armies chasing Napoleon's might through France and Spain. By April 1814 Napoleon was defeated.

Although war was to flare up a year later in the brief and disastrous Battle of Waterloo, the main war for the Iberian Peninsular was over.

Over the winter of 1813/14, British, Spanish and Portuguese forces chased Napoleon's troops over the Pyrenees and into France. As they swept northwards, the forces had to deal with the isolated French garrisons they came across.

One of these was the citadel of Bayonne, situated on the northern bank of the River Adour, six miles upstream from the sea. This was garrisoned by the French under General Soult. If Bayonne was left unmolested, then the French troops within could cause great difficulty for the allies.

To do this, the wide and fast-flowing River Adour had to be crossed. British guns fought off the French sloop and gunboats that patrolled the river, forcing them to safety further upstream. Then sixty men made their way across to the French bank on a pontoon, and the French picquet retreated without combat.

A hawser was then stretched across the river and the remaining pontoons made into a raft, by which 500 British troops and some rockets made it across. But this was not ideal: the crossing could only be made at the slack water of low tide, and the rafts were a slow and vulnerable way of getting men and materials across.

Unlike today, the mouth of the Adour was a mass of sandbanks that were difficult to navigate, and the French had removed the poles that marked the only channel. The allies had commandeered scores of boats, including Spanish chasse-marees, and several of these were lost trying to find a route into the river. Eventually such a route was found, although the final attempt had to wait until the next day.

At the next high tide on the 24th of February, British warships headed upstream to chase off the damaged French ships. This was followed by a long stream of boats, crewed mainly by Spanish sailors, with British engineers on board to manage the later tasks. They made their way across the breakers and headed upstream for three miles to reach a point halfway between the citadel and the sea, where retaining walls narrowed the swift-flowing river to 800 feet in width.

Twenty-six of the chasse-marees were moored in a line across the river, and planks and cables strung across them to form a floating bridge that could cope with the fourteen-foot tides. This was protected with booms, and was used to get the rest of the army across the river.

This bridge has fascinated me for years: it was an ingenious way of solving a problem, and yet this postscript to the Napoleonic wars is little known. To my surprise, I found an engraving, reputedly from 1823, showing the bridge. This means that it remained in place for at least nine years after the battle.

Like all battles, it was won more by the side that made the least mistakes: the French had thought the river unnavigable by the British so had not guarded the mouth, and they had not thrown everything into repulsing that first landing of sixty troops.

Sadly, the battle turned into a siege of the citadel that lasted until the end of the war a few months later. But a siege was good enough for the British, as it bottled up the French forces.

So tonight I will raise a toast to the brave men and boys from three nations who risked their lives to build that humble bridge of boats.

The bridge of boats below Bayonne, May 1823

Book review: "The map that changed the world", by Simon Winchester.

William Smith is today widely acknowledged as one of the founding fathers of geology. Smith is rightly acknowledged as a massively important figure in the formative science of geology, although he is not as famous as James Hutton, whose unconformity at Siccar on the Berwickshire coast gave dramatic clues to Earth's history.

He came up with the concept that seemingly-identical bands of rocks could be differentiated by the types of fossils found within, and that any band of rock containing the same fossils had to have been laid down at the same time, wherever it was found in the country. He also noticed that many fossils appeared to get more complex as rocks get younger, a concept that aided Darwin's later work. In addition, he worked out that layers of rock are mostly found in the same order; if a certain sandstone lies above a certain coal measure in one area, you can assume that if you find the same sandstone in a different area, coal will probably lie underneath.

The importance of these theories for industry are all too obvious; indeed, Smith could achieve the seemingly miraculous feat of predicting what rocks could be found. If a landowner wanted to know if there was coal under his land, then Smith could tell him without any costly digging. The importance of the theory on the Christian church are harder to understand from the modern perspective, but these problems are outlined well in this book.

From humble beginnings, Smith became an engineer and drainer, responsible for water management and canals in a similar manner to one of my heroes, William Jessop (who is actually mentioned in the piece). These jobs gave him the opportunity to travel and to compare rocks, whilst his work on the Somerset Coal Canal gave him the chance to examine a transect of a geologically interesting part of the country.

Despite those humble beginnings, Smith's ideas and concepts developed a worthy following. His first geological map was of the are around Bath in 1799, and by 1815 he had produced the first complete (if much delayed) geological map of England and Wales.

It is here that this book becomes more of a paean than a scholarly work. Mr Winchester comes across as a little too fond of his subject. Either that, or a misplaced need to impose drama, causes what was a complex grey situation to be painted as black and white. Anybody who opposes Smith becomes an unsympathetic character in the book; even a friend who slightly wrongs him is treated as if he were a little child who eventually learns the errors of his ways.

In 1819 Smith was thrown into a debtor's prison in London. This book puts this mainly down to a competition with a plagarised copy of his map released by the recently-formed Geological Society of London. However whilst reading the book it is obvious that Smith was the architect of his own misfortune, with several failed business ventures unconnected to mapping, his delays in creating maps and books, and his rather ostentatious habit of buying houses that were rather too grand for his income. The book admits that his friends and admirers tried to help and gave him money, but that his debts were too great.

I also wanted to know more abut Smith the man. He married a younger woman, Mary Ann, who the book claims was mentally ill with something akin to nymphomania and ended her days in a mental institution. Whilst it seems that the parts of Smith's diaries containing references to Mary Ann was later expunged, and his nephew and biographer did not mention her much, I wanted to know more, even if it was mainly supposition. Smith appears to have stood by his wife, and her to him, throughout their travails; I wanted to know if that was really the case, and why that may have been.

Likewise, Smith took in his orphaned nephew, John Phillips, who himself became a famous and well-respected geologist. I wanted to know a little more about their relationship, and Phillips' view of his uncle.

By the time of Smith's death, the leadership of the Geological Society had changed and Smith's key work in the formative science was acknowledged. he was awarded plaudits, praise and even a pension of £100 a year from King William IV.

It is also made clear that others were working on how the Earth was formed at roughly the same time, most notably the aforementioned James Hutton. It would have been nice for the author to mention how Smith's work and theories fitted in around those of the other geological titans. For instance, did Hutton influence Smith's work? If so, then it is hardly to the detriment of Smith's theories or his maps.

All the valedictory words in this book could be replaced by just two pictures: Smith's 1815 geological map is reproduced within the inside cover, and an equivalent modern map within the back cover. Flicking between these two, and the similarities between them, shows better than any words Smith's achievement. For this reason, it would have been nice if they had been available as larger fold-outs, so they could more easily be compared.

I would give this book four out of five stars: geology can be a very dry subject, and Mr Winchester explains the terminology well and without assuming too much background knowledge. However it could have done with more focus on Smith the man, and less blaming others for Smith's own misfortune.

HS2 news

There have been some possible developments with regards to HS2's scope and cost reductions. But first, I should set the scene a little.

The HS1 line from the Channel Tunnel to London terminates at St Pancras station, in the north of the city, whilst the planned HS2 line from the north to London will end at Euston, about half a mile to the west of St Pancras.

It was envisaged that most of the demand on HS2 would be trains to the north from London. To enable a few through trains from the continent, a £400 million link was planned from the HS1 line north of St Pancras to the HS2 line north of Euston. This is a very limited kludge: it is a single-track alongside the existing North London Line. To make matters worse, the HS2 line is expected to be very busy in terms of services when it opens, meaning that there would be few opportunities for such trains anyway.

It was reported in the Times at the weekend that this link may now be dropped. I am fairly unconcerned about this: if such a link is to be built then it really should be done properly. Scrapping the link costs will decrease by £400 million, and many of the objectors such as Stanley Johnson (Boris Johnson's father) with houses near the link route may become more muted.

Politically, it is much more important. One of the selling points of HS2 to northern constituencies is that they would be able to have direct rail services from Europe. With the abandonment of the link, this promise is more or less broken. Worse, it will be much harder to build after phase 1 without causing massive chaos on the operating line. If it is to be built, it really needs to be built at the same time as phase 1.

In other news, the Guardian has an interesting article on the way that HS2 costs could be reduced by looking at the continental experience.

A350 news

The new Airbus A350 is appearing at the Singapore Air Show, six months after its first flight. The BBC have a video of it at the show, although sadly it is stationary on the ground rather than in the air.

The A350's test flight program appears to be going well; there has been little of the noise that the 787 tests caused, or indeed, no in-flight fires. The two test-flight planes are each getting 100 flight hours per month, with over 1,000 flight test hours completed in total. The main 'hot' and 'cold' tests have also been successfully completed in Bolivia and Canada respectively.

Let's hope the rest of the program goes well, and that Airbus have a competitive challenger to Boeing. And indeed, that Boeing sorts out its problems with their 787.

Dawlish

I'd like to pay tribute to the engineers that are currently working to fix the railway line at Dawlish, where the sea wall that protects the railway line and houses has been breached by the recent bad weather.

When I first saw the pictures, my inexpert reaction was that the house that was left right at the edge of the breach would have to be demolished. But their work has saved it for the moment - they laid sections of the damaged track against the remaining earth, and are covering the lot with shotcrete (sprayable concrete) to form a temporary barrier.

In the meantime, they are placing 20-foot shipping containers along the recently-installed concrete toe of the wall, which is undamaged, and filling them with rubble to act as barriers to protect workmen from the worst of the waves. This is an act of genius, and will hopefully allow them to speedily rebuild this breach.

It is at times like these that engineers really come into their own, and I've been really impressed with the work that they are doing. They've got some really good people on the job, despite other problems on the network caused by flooding.

It's also given me a reason to do a little research on the sea wall, which I know well from my childhood. The wall has withstood the weather over the last 160 years well, despite the infrequent breaches. In fact, the line is more often closed because of rock falls from the cliffs on the other side of the railway.

Let's hope the solutions modern engineers come up with last for a similar period.

The seawall near the breach, seen in happier times in 2003.

Periodic table for writers

Just for fun, here is a link to a periodic table for writers, It captures some of the many tropes in writing and attempts to categorise them into headings such as Structure, Archetypes and Villains.

Some of my favourites:

JTS (Jumping The Shark)
5MA (Five Man Band)
PMD (Person of Mass Destruction)
ARC (Story Arc)
FLA (Flanderization)

Stories can combine several of these categories, for instance the film 'Highlander' has a Hero's Journey in which the Hero, imbued with a power that makes him The Chosen One, is taught how to use that power by an Eccentric Mentor in order to beat a Complete Monster and Save The World.

There is more to storytelling than is detailed within the table, but it is the first time I have seen such a comprehensive and easy-to-use reference.

Book review: "Moon over Soho" by Ben Aaronovitch

When jazz musicians start dying of natural causes shortly after completing their sets, DC Peter Grant tries to find connections between the men. Can he find the answer before his own famous jazz-playing father becomes a victim?

I've read (and reviewed) the first book in this series, "Rivers of London", and thought it was a brilliant read. In it, a probationer constable with the Metropolitan Police, Peter Grant, discovers that there is a magical side to life in the capital. He becomes an apprentice to Nightingale, the last magician in the force, and moves to live in the Folly, a grand house in Central London.

This second book is slightly less inventive than the first (the narrative world has already been created), and the plot is slightly less manic and easier to follow. We learn more about the central characters: from Nightingale's activities in the Second World War, to Molly, the servant who refuses to leave the Folly. This adds a depth that was missing in the first book, especially as a villain is created that could last through several more books.

There are a couple of places that an editor could have done a better job - for instance the explanation of  a 'nominal' in the HOLMES2 police computer is repeated, and there are a couple of other repetitions. Aside from these, the prose is fresh and the descriptions vivid. DC Grant's voice is brilliantly compelling and I found myself bathing in it: he is a truly great character, and the first-person voice is lively and realistic.

I really don't like jazz, but I found the jazz side of the plot was cleverly more about the personalities than the music - especially the band that hang around DC Grant because of his father's fame. It was well handled, and to my surprise I found it appealing. It takes skill to write a plot that revolves around the world of jazz, without annoying someone who has no love for the music.

The first book in the series was laugh-aloud funny, and that it continues in this sequel with lines such as: "Nobody kills a suspect in a police station and gets away with it - at least nobody without a warrant card."

I would give this book four out of five stars, and I look forward to reading the next in the series: "Whispers Underground".

Blaming the wrong person

In his usually excellent blog, Francis Pryor (of Flag Fen and Time Team fame) talks about comments from the chairman of the Environment Agency in which the chairman says that the countryside might have to have flood protection funding removed in favour of towns and cities.

Below is part of Francis Pryor's blog:

I was astonished to hear that the chairman of the Environment Agency has written in the Daily Telegraph that when it comes to flooding we must decide between town and country – and this from a political party that is supposed to number rural people among its supporters (but that doesn't include me, I hasten to add!). I cannot believe what is being said.

I have some sympathy with his core point: I'd like to see more funding for flood protection of the coast and low-lying areas. But he is making a rather dramatic error in equating the chairman of the EA with the government. For the chairman is Lord Smith of Finsbury, AKA Labour peer Chris Smith, who was Labour's Secretary of State for Culture, Media and Sport during the early years of the Blair government. He was appointed as chair of the EA in 2008.

Blaming this government for the comments of a Labour peer who was made head of a quango by a Labour government seems rather misguided.

Sadly, Francis Pryor does not allow comments on his blog, so I can't comment there directly.

HS2 news

It appears that Labour may be looking to delay the passage of the phase one bill for HS2 through parliament, so they can scrap it if they come into power at the next election.

Linky (telegraph)

Politically, there are several things to say about this:

1. Labour should have the courage of their convictions, and either come out in favour or against the project.
2. Many northern - Labour - councils want HS2, which may explain the two-faced approach by the opposition front bench.
3. Any such delays means the project will cost more.

In other news, the Crossrail project is halfway complete, and on budget.

A walk, a walk, my kingdom for a walk ...

A few days ago, I wrote in a post that I was fed up with giving in to my dodgy back and wanted to wean myself back onto longish distance walking. I had some formative criteria which are reproduced below:

1. Between 10 and 15 miles;
2. Preferable on a good surface due to the weather;
3. Has public transport at regular intervals in case my back goes
4. Optionally has lots of interest to see and do.
5. Preferably within easy access of Cambridge.

As today was a day that I could skive off, and also one where the forecast was good (it has been rare for the two to combine this winter), I decided to do a walk. And in the end, I decided to walk into Cambridge. There is a handy bridleway that runs all the way from Bourn into the city, but this is never more than a mile or two from the road and bus stops. It would be an eleven mile walk - result!

Where does the field end, and the path begin?
Yes, that is a bridleway on the right.

The first problem is the bridleway, which I have cycled along many times, had more in common with a canal. Not just any old canal, but a canal that had been allowed to silt up for a few decades. To my surprise there were no shopping trolleys in it. The wet winter has really had a terrible effect on the ground, and I merrily slipped and slid my way along. Eventually, looking more like the creature from the Black Lagoon than a human, I reached Cambridge and went into my favourite hostelry, the Baron of Beef.

I had done eleven miles (twelve including walking with my wife to her workplace), my back was aching but manageable, and everything was good. I had a couple of pints, and all I needed to do was amble through town to the bus that would drop me a few yards from my door.

But no. I am a long-distance walker, and that means that such a humdrum solution was anathema. Instead, I lifted my rucksack onto my back and headed back. The road route along Madingley Road seemed more sensible than risking the swamp once more, and so I headed off down the road, knowing that I could always catch one of those nice, warm buses that drive virtually to my door.

Yeah, right. After twenty-two miles I arrived back home overheated, dehydrated (yes in February) and with two hips that were hurting how I think buggery must feel. The good news is that although my back is aching, it has not spasmed.

So of my criteria above: I broke 1,2 and 4 (I drive down Madingley Road regularly, and know it all like the back of my hand. Therefore even the wonders of the outside of the American Cemetery or the windmill hold no particular joys).

I think I may limit my next walk to fifteen miles.

Yeah, right ...

Carbon Capture and Storage

During his lamentable time in charge of the Department of Environment and Climate Change, Ed Miliband brought in a rule stating that any new coal-fired power station should use carbon capture technology (CCS). This move was apparently a surprise to many in the department, and came after he was heckled by Pete Postlethwaite whilst at a film première in London.

The rule has been a disaster, and has essentially stopped any coal fired power stations from being built in the UK. Whilst this may be good for the environment, it should be noted that ten new coal-fired stations will start producing power in Germany over the next few years.

Coal power stations are cheap and brilliant at producing baseload power. The downside is that they are dirty and produce several greenhouse gasses, for instance CO2. CCS involves splitting carbon dioxide from gasses and placing it into a geological reservoir; this can be depleted gas or oil geological formations, or even the deep ocean. It has been used for many years in a couple of ways:

1. In some gas fields, the carbon dioxide that is raised with the gas is stripped out and put back into the formation. 
2. In some oil fields, CO2 is injected back into the reservoir to maintain pressure and keep the oil flowing. This is known as Enhanced Oil Recovery. 

This has led to the idea that CO2 can be stripped out of the flue gasses from coal power stations and then transported to a reservoir for storage, Here in the UK, the most obvious place are the gas and oil fields that have been depleted.

On the face of it, CCS seems like a brilliant idea: capture the atmospheric pollutant. So what are the problems?

1. It has rarely been done on a large scale, with the reservoirs situated far away from the generators. When it is used, it is mostly used in gas or oil fields as mentioned above. 
2. It dramatically reduces the efficiency of the power plants. Depending on the type of plant and the location of reservoir, the stripping and transport of the CO2 can take 15 to 45% of the power produced by the power station. 
3. It is hideously expensive. 
4. I have grave doubts about the capacity and security of the reservoirs. The reservoirs may have stored natural gas for millions of years, but that was before they were made into pincushions and emptied. And if CO2 does degas in a big way, it is much worse - and deadlier - than natural gas as it is slightly heavier than air. The Lake Nyos tragedy shows these dangers. 
5. I think a little too much attention is being put on CO2 as an atmospheric pollutant, especially in comparison to other greenhouses gasses. Would we be spending the vast sums CCS would demand on the right target? 

I don't know what the answer is to green baseload energy, but I'm fairly sure that it's not large-scale CCS on power generators.

If we do go ahead with it, than there should be long-term and reliable checks on the integrity of any reservoirs, and monitoring for any leaks, along with warning systems to be used in the case of large-scale leaks.

Tunnel vision

As some of you may have noticed, I am a tunnel junkie. Whether canal or railway,Victorian or modern; hand-dug or submersed tube, I love them all.

It was therefore with interest that I found Graeme Bickerdike's video on the excellent 'Forgotten Relics' website. The video explains the way some of the tunnels were built in Victorian times, and is well worth a watch if you're into such things. The production standards are surprisingly high for such an esoteric video, and Graeme does a splendid job as presenter.

If you want to know more, then there are a couple of books available on-line that also detail Victorian tunnelling techniques:

Railway Tunnelling in Heavy Ground (1879)

and

Practical Tunnelling (1896), which also had some chapters by the famous D.K. Clarke.

They make you realise how amazing the modern Tunnel Boring Machines are, and the way we can bore so many miles of tunnels deep under our capital city without any deaths of major injuries.

The man and boys who built our canal and railway network - now so dismissively called Navvies - really were a breed apart.

I hope you haven't found this a boring post ...

Book Review: "Natural Causes" by James Oswald

When a young girl's disembowelled and mummified body is found nailed to the floor of an old house in Edinburgh, Detective Inspector McLean is assigned the case. It soon becomes clear that the girl died sixty years before. But if that is true, then why are similar murders occurring?

I bought this book on an impulse; it was on a display stand whilst I was queuing to buy another couple of books. The front cover proclaimed it to be a Richard & Judy Book club winner, and that it was by "The new Ian Rankin"

I see the latter as high praise indeed, so I bought it and started reading. And yes, the book could almost have been written by Rankin. It is set in contemporary Edinburgh, and features a newly-promoted Detective Inspector, Anthony McLean.

Sadly, Mr Oswald does not manage to get the same 'feel' of Edinburgh that Rankin does. Rankin treats the city as if it was a living creature, and manages to perfectly capture the soul of the city he loves. In comparison, this book seems to present a more one-dimensional view of the city and its people. Despite this, it was a very good effort.

As usual with such central detectives, he has a tragic history which is slowly unveiled: his parents died when he was four, and his fiancée was tragically murdered before their marriage. Also like many detectives, he argues with his superior officers, is unattached and not particularly interested in a partner. And as is also common, he has a partner (or at least sex) before the end.

The book also features lots of crimes. There are at least a dozen deaths, all singular, many of which are disembowlings. Add in a kidnapping and a hit-and-run, and you probably have more murders than occur in Edinburgh in a year. And yet the investigating officers (excepting the hero) do not link the deaths.

Interestingly, the author's text at the end of the book, and reader's comments, imply that the first chapter in this paperback edition is not the same as in earlier hardback editions - he has significantly altered it. The original is now reproduced at the back. If this is correct, then it is an interesting course to take: which one is the real story? This matters, as the original first chapter was a much darker beast - it put many people off reading the book, which is why he changed it.

In terms of prose, this book is better than Rankin's worst Rebus books, but worse than Rankin at his best. Although that might sound backhanded, it is meant as a compliment

However:

**** Spoiler ***

Despite the above, this book was a real disappointment. Everything about the cover screams moody, dark crime novel, with heinous deeds waiting to be solved by an intrepid detective, preferably along with a gullible sidekick. And that's exactly the way "Natural Causes" starts. Unfortunately the supernatural starts to creep in, until eventually the culprit turns out to be a demon.

Such genre shifts are tricky to pull off. The reader has had turkey for the Christmas dinner, and instead of a nice fruit-filled Christmas pudding for dessert, he gets an ice-cream sundae. Some will enjoy it, but others will feel let down.

In my case, I felt let down. I have read other detective stories where, midway through the tome, the plot points towards a supernatural cause, only for a very rational explanation to come through in the end. They can be tremendous fun as you try and work out how a seemingly inexplicable crime has been committed. As I was reading this book I was considering all the possible drugs, mental illnesses or threats that could explain the crimes. In the end, as the blurb says, it is the most irrational answer.

It would be better if it had been left open to either a natural or supernatural cause, and a quick check on Amazon shows that some people think it has. But I cannot see how the events could have unfolded as described, unless the protagonist is insane or an exceptionally unreliable narrator. Using the supernatural entity as the criminal is also a lazy way to write - you can get away with anything. It is one of the most intrusive deus ex machina I have read for some time.

It is not that I am against supernatural crime thrillers: I loved the wit and inventiveness of Ben Aaronovitch's 'Rivers of London'. It is just that the genre shift proved much too sharp for me.

For prose, I would give this book four out of five. As a detective story, one out of five.