Category: Book Reviews

Reviews of books featuring a summary of the book and links to related material

Apr 17 2012

Book Review: Stargazers by Fred Watson

41W3OswkqxL._SS500_This post is a review of “Stargazers:The Life and Times of the Telescope” by Fred Watson. It traces the history, and development of the telescope from a little before its invention in 1608 to the present day.

The book begins its historical path with Tycho Brahe, a Danish astronomer who lived 1546-1601. He built an observatory, Uraniborg, on the Danish island of Hven in view of his patron, King Frederick II of Denmark. Brahe’s contribution to astronomy were the data which were to lead to Johannes Kepler’s laws of planetary motion and ultimately Isaac Newton’s laws of gravitation. On the technical side his observatory represented the best astronomy of pre-telescope days with the use of viewing sights, his Great Armillary with it axis aligned with that of the earth and graduated scales to measure angles. Watson also cites him as a first instance of a research director running a research institute – alongside the observatory he ran a print works to disseminate his results.

The telescope was first recorded in September of 1608, when Hans Lipperhey presented one to Prince Maurice of Nassau in the Netherlands. Clearly it was a device of its time since in very short order several independent inventions appeared, Galileo constructed his own version which led to his publication of “The Starry Messenger” in 1610 which reports his observations using the device. The telescope grew out of the work of spectacle makers; there are some hints of the existence of telescope-like devices in the latter half of the 16th century but these are vague and unsubstantiated. Roger Bacon and Robert Grosseteste both conceived of a telescope-like device in the 13th century, around the time the first spectacles were appearing. Although there are a few lenses from antiquity there is no good evidence that they had been used in telescopes.

The stimulus for the creation of the first telescopes seems to have been a combination of high quality glass becoming available, and skilled lens grinders. The lens making requirements for telescopes are much more taxing than for spectacles. The technology required is not that advanced, if you look around the web you’ll find a community of amateur astronomers grinding their own lenses and mirrors now using fairly simple equipment, typically a turntable with a secondary wheel which produces linear motion for the polishing head back and forward across the turning lens blank. The most technologically advanced bit is probably captured in the first step: “acquire your glass blank”.

Through the 17th century refracting telescopes were built of ever greater length in an effort to defeat chromatic aberration which arises from the differential refraction of light as a function of wavelength (colour) – long focal length lenses suffered from less chromatic aberration than the shorter focal length ones which would allow a shorter telescope. Johannes Hevelius made telescopes of 46m focal length (physically the telescope would be a little shorter than this), mounted on a 27m mast; Christiaan Huygens dispensed with the “tube” of the telescope entirely and made “aerial telescopes” with even longer focal lengths, up to 64m.

It was known through the work of Alhazen in the 10-11th century, and others, that reflecting, curved-mirrors could be used in place of lenses. A telescope constructed with such mirrors would avoid the problem of chromatic aberration. However, the polishing tolerances for a reflecting telescope are four times higher than that of a lens. Newton built the first model reflecting telescope in 1668 but no-one was to repeat the feat until John Hadley in 1721.

Theoretical understanding of telescopes developed rapidly in the 17th century both for refracting and reflecting telescopes, indeed for reflecting telescopes there were no fundamental advices in the theory between 1672 and 1905. The problem was in successfully implementing theoretical proposals. Newton claimed that chromatic aberration could not be resolved in a refracting telescope, however he was proved wrong by Chester Hall Moor in 1729, and somewhat controversially by John Dollond in 1758 who was able to obtain a patent despite this earlier work (which was defended aggressively by his son) – the trick is to build compound lenses comprised of glass of different optical properties.

Also during the 18th century the construction of reflecting telescopes became more common, William Herschel started building his own reflecting telescopes in 1773 with the aid of Robert Smith’s “Compleat system of opticks”. Ultimately he was to build a 40ft (12m) telescope with a 48 inch (1.2m) mirror in 1789, supported by a grant from George III. During his lifetime Herschel was to discover the planet Uranus (nearly called George in honour of his patron), numerous comets and nebulae. At the time “official” astronomy was more interested in the precise measurement of the positions of stars for the purpose of navigation. Herschel was to be followed by Lord Rosse with his 1.8m diameter mirror telescope built in 1845 at Birr Castle, this has been recently restored (see here). He too was interested in nebula and discovered spiral galaxies.

During the 19th century there were substantial improvements in the telescope mounts, with engineers gaining either an amateur or professional interest (men such as James Nasmyth and Thomas Grubb). Towards the end of the century photography became important, which placed more exacting standards for telescope mounts because to gain maximum benefit from photography it was necessary to accurately track stars as they moved across the sky to enable long exposure times. This is also the century in which stellar spectrography became possible with William Huggins publishing the spectra of 50 stars in 1864. Léon Foucault invented the metal coated glass mirror in 1857 which were lighter and more reflective than the metal mirrors used to that point. As the century ended the largest feasible refracting telescopes with lens diameters of 1m were just around the corner, above this size a lens distorts under its own weight reducing the image quality.

In 1930 Bernhard Schmidt designed a reflecting telescope which avoided the problem of aberrations away from the centre of the field of view making large field of view “survey” telescopes practicable. As a youth in the 1970s I learnt of the 200-inch (5 metre) Hale telescope at Mount Palomar, since then space telescopes able to see in the infra-red and ultra-violet as well as the visible have escaped the distortion the atmosphere brings; adaptive optics are used to counteract atmospheric distortion for earthbound telescopes and there are “distributed” interferometric telescopes which combine signals from several telescopes to create a virtual one of unfeasible size.

Watson mentions briefly radio telescopes and in the final chapters speculates on developments for the future and gravitational lensing – natures own telescopes built from galaxies and spread over light years.

I enjoyed “Stargazers” as a readable account of the history of the telescope which left me with a clear understanding of its principles of operation and the technological developments that enabled its use, it also provides a good jumping off point for further study.

Footnotes

My Evernotes for the book are here, featuring more detailed but slightly cryptic notes and links to related work.

Apr 06 2012

Book Review: Adapt by Tim Harford

adaptThis is a review of “Adapt: Why Success Always Starts With Failure” by Tim Harford which puts forward the thesis that “trial and error” is the only way forward for complex endeavours to succeed.

Opening up to trial and error is divided into three tasks:

  • Providing scope for variation in what you do;
  • Establishing whether or not a variant has been successful;
  • Making sure that you have systems in place to cope with failure.

Each of these tasks is illustrated with a wide range of real-life examples: using the Iraq War to highlight the difficulties of running “trial and error” inside control structures that are designed to take in information, channel it to the top of the organisation and provide a channel back from the top to the bottom. Donald Rumsfeld, apparently, would not refer to the “insurgents” as “insurgents” so hobbling the US’s ability to fight an “insurgency”.

Alongside these major case studies are smaller ones, such as on Jamie Oliver’s school dinners which showed that feeding children healthy food at primary level led to measurably better outcomes in education and attendance than comparable groups not within the scheme, you can see the study here.

There is also a section on using a carbon tax to address anthropogenic climate change, this fits in as a way of making selection possible by providing a simple measure of “success”. Harford is scathing of the ”Merton Rule” which demands that new build of above a certain size generate 10% of their electricity onsite by renewable means. As put by Harford this means installing capacity rather than demonstrating capacity which has lead to the use of dual fuel systems (nominally able to take renewable fuel) that are ultimately only used with non-renewables so providing no benefit at all.

The Piper Alpha and Three Mile Island accidents are provided as examples of the importance of being able to fail safely, they didn’t or rather Piper Alpha didn’t – arguably Three Mile Island just about failed safely. This was linked to failings in the financial system where large organisations, such as Lehman Brothers failed in a matter of hours with administrators scrabbling around frantically to come up with a controlled-landing plan. This is failure at large scale, but there is also coping with failure at the personal scale. For example, using “Deal or No Deal” as a model system in which contestants can “lose” which changes their estimations of risk for subsequent play for the worse.

One issue with “trial and error” is that the proponents of any method are often so convinced of the value of their method that they feel it immoral to subject anyone to an “inferior” alternative in order to conduct a trial. This is highlighted with a story about Archie Cochrane, pioneer of the randomised control trial in medical studies. He had been running a study on coronary care, comparing home-based care to hospital care. This had met with some opposition, with medics insisting that the home-based arm of the trial was unethical because it was bound to be inferior. When results started to come in it turned out that one branch of the trial was inferior to the other – Cochrane misled his colleagues into believing it was the home-based arm that was inferior – they demanded that it should be closed down but were rather silent when he revealed that it was in fact the hospital-based arm of the trial that was inferior!

Harford also discusses funding for research, in particular that blue-skies research could not be valued because the outcomes were so uncertain, highlighting the success of the Howard Hughes Medical Institute which funds speculative biomedical research in the US. What he goes on to say is that the use of prizes is a way out of this impasse. Using as an example the Longitude Prizes, his presentation plays up the friction between Harrison and the Board of Longitude. The Academie Des Sciences also ran prizes but until recently the method had been out of favour for approaching 200 years. The recent revival has included things like the DARPA challenges for self-driving cars, Ansari X Prize, the Bill and Melinda Gates Foundation prize for vaccines and Netflix’s film selection challenge. These have been successful, however it’s difficult to see them finding more general favour in the academic community since the funding is uncertain and appears only after researchers have expended resources rather than receiving the resource before doing the work.

From a practical point of view “trial and error” happens in the private sector, if not within companies then between. In the voluntary sector it has taken some hold, for me some of the more compelling examples were by the “randomistas” studying the effectiveness of aid programmes. In the public sector “trial and error” is more difficult: there is less scope for feedback on the success of a trial – you can’t meaningfully count customers through the door, or profits made, so there is a need for proxy measures. Furthermore, the appearance of failure carries a high price in the political sphere. This is not to say it shouldn’t happen, simply that “trial and error” face particular challenges in this area.

I like the central thesis of the book, it fits with my training as a scientist; my field allows for more direct experimentation than a randomised trial but the principle is the same. It also has pleasing parallels with biological evolution, which Harford explicitly draws. The book is well referenced, in fact I hit the end unexpectedly as I was reading on a Kindle – I couldn’t “see” the length of the end notes!

Mar 25 2012

Book Review: The Great Arc by John Keay

TheGreatArcThis is a review of “The Great Arc: The Dramatic Tale of How India Was Mapped and Everest Was Named” by John Keay. This book does exactly what it says in the lengthy subtitle: describe the Great Triangulation Survey of India which was conducted in the first half of the 19th century.

It fits together with “Map of a Nation” by Rachel Hewitt and “The Measure of All Things” By Ken Alder. The former describes the detailed mapping of the United Kingdom by the Ordnance Survey, whilst the later describes the measurement of the Paris meridian by Méchain and Delambre. Of the three surveys the French one had been completed first at the beginning of the 19th century whilst the mapping of the UK was going on at the same time as the Indian survey.

The book is centred around the Great Arc survey originally proposed by William Lambton at the beginning of the 19th Century. Lambton’s aim was primarily to measure a meridian (a line of longitude), in the same manner as the Paris meridian in order to gain more information on the shape of the earth (geodesy). For his sponsors in England and the administration of India the survey served as a military and commercial exercise. Military action is often a spur to survey, since getting your troops and their equipment from point A to point B and ensuring they prevail over any forces they come across on the way is a high-value activity which is greatly assisted by the provision of accurate maps. Surveying is also invaluable when you are planning infrastructure such as roads, canals and railways.

The survey came a time when the British relationship with the area now known as India was changing from a trading one based on outposts to one in which the British took territory militarily. The Triangulation Survey was not exhaustive, it comprised a central spine (The Great Arc) running along the 78th meridian up through the tip of the Indian peninsular to the edge of the Himalayas with regular “cross-bars” running from West to East, towards the north an array of parallel meridians were also measure. (You can see a map here). The aim was to use this survey to constrain further local surveys.

The Great Arc survey was a great endeavour, taking 40 or so years in total, after Lambton died in 1823 George Everest took on the job of leading the project. Lambton seems to have been a pleasant sort of chap who went a little native, disappearing from the view of his sponsors. Everest, on the other hand, appeared to be a complete git – being abusive to most of his subordinates and apparently also winding up his superiors.

Much of the activity in the book is in common with that which took place during the surveys of France and the United Kingdom. Laying out base-lines: distances measured directly on the ground by means of rods or chains used to pin down the distances in the “triangulation” which is a collection of angular measurements at the vertices of an array of triangles. Once again the precision is impressive, two 7 mile baselines measured out 200 miles apart agree with the triangulation measurement to within a few inches. Angular measurements were made using a theodolite, Keay labels the one used in India as the “Great Theodolite”, which I thought was a term reserved for the Ramsden device used in the UK (we can’t all have a Great Theodolite!).

The Indian survey presented different challenges in the form of the wildlife (tigers, scorpions etc) but also disease. The rate of attrition amongst the surveyors, particularly as they traversed jungle was terrible. The book is not explicit about figures but in the later stages of the survey something like a thousand men were involved and a couple of hundred of those died of disease. Lambton and later Everest both suffered from recurring bouts of malaria.

The “discovery” of Mount Everest and the tallest peaks in the Himalayas was somewhat incidental to the main thrust of the survey. It had become clear in the first decade or so of the 19th century that the Himalayas were the tallest mountains in the world but their precise height was uncertain. Political difficulties with Nepal, their location far from the sea and their immense size meant determinations were poor. Indeed at the time of the beginning of the survey the height of Mont Blanc in Europe was only know to within a thousand feet or so of its currently accepted value. It wasn’t until 1856, after the Great Arc had been completed and Andrew Scott Waugh had taken over the survey that Mount Everest (known at the time as Peak XV) was measured and Waugh proposed Everest be its name. (Everest is apparently pronounced Eve-rest rather than Ever-est, and the man himself was very particular about this).

Put beside “Map of a Nation” and “The Measure of All Things”, “The Great Arc” is a nice, brief introduction to the theme of triangulation surveys and geodesy which covers measuring the height of mountains in a bit more detail than the other two.

The Great Arc survey, along with the French meridian survey fit together with the earlier French Geodesic Mission to Peru by Condamine and Bouger around 1735, which is described in “Measure of the Earth” by Larrie G. Ferreiro – I’ve added this to my wish list.

Footnotes

You can see my Evernotes on The Great Arc here.

Mar 18 2012

Book Review: Decoding the Heavens by Jo Marchant

DecodingtheHeavens“Decoding the Heavens” by Jo Marchant is the story of the Antikythera Mechanism, a mechanical astronomical calculator dating from around 100BC which predicts the motions of heavenly bodies including the sun, moon and various planets. The best way to understand how the device worked is through videos relating to this book (here) and, rather more slickly (here).

The Antikythera Mechanism was recovered off the coast of the island which provides its name in 1900. The wreck from which it was recovered was also carrying a large number of impressive bronze and marble statues, for example the Antikythera Ephebe. It is believed it was sailing from the Asia Minor coast to Rome, carrying the spoils of war. The wreck lies at a depth of 60 metres which is deep for the technology available at the time, the distinctive metal-helmeted diving suit. It was discovered by the crew of Captain Krontos, who were sponge-divers. As such they did a very risky job, Marchant reports that between 1886 and 1910 around 10,000 divers died from the bends and a further 20,000 were paralysed.

Once they had discovered the wreck they reported it to the Greek government who organised the salvage operation, at the time it was one of the first marine archaeological salvages – it was preceded  in 1884 by a speculative operation in the straits of Salamis which had recovered little. By the 1950s hundreds of wrecks were known in the Mediterranean. Marchant states that this is the first ever attempt to salvage artefacts from a sunken ship, I’m sceptical of this claim – it’s only true for very narrow definitions of each word – Edmond Halley, for example, had a company offering to salvage treasure from sunken ships in the 1690s.

It is curious how little regarded the Anthikythera Mechanism has been over the hundred or so years since its discovery. A measure of this is that the Athens National Museum, where it is kept, were still finding bits of it in 2005! This re-discovery is in some sense understandable, the Mechanism presents a rather unassuming appearance when compared to the statues with which it was found furthermore curating appears to have sharpened its act up over the years. A second reason is that it almost has the air of a fake about it, no other mechanism of comparable complexity was known until around 1000AD, and there was little written evidence for the existence of such devices.

The book works through the interpretation of the mechanism chronologically by researcher, starting with the initial interpretations made by John Svoronos and Pericles Rediadis (1903), Konstantin Rados (1905), Albert Rehm (1907) and John Theophanidis (1934). These are covered quite briefly. These initial studies were based on an exterior view of the fragments and small amounts of visible text, of which more became visible as cleaning attempts were made. It’s worth highlighting here that the mechanism was covered in text, both labels and operating instructions although originally little of this text was discernable. From these studies the mechanism was related to astronomical equipment such as the astrolabe, but was clearly different since it had a more complex clockwork-like mechanism. This chronological approach means that the reader gets a fragmented view of the device (with reverses in interpretation), as the story unfolds. There is also a degree of dramatisation of the story (e.g. “Shit,” said Roger Hadland) scattered through the book, I must admit to finding these rather grating but they are relatively sparse.

After the initial investigations there was a hiatus, with interest appearing to restart in the 1950s possibly spurred by a visit by Jacque Cousteau to the wreck in 1953. Derek De Solla Price was the next to attempt an analysis aided by x-ray imaging of the mechanism which was not available in earlier times. Price was Professor of the History of Science at Yale, in addition to his work on the Antikythera Mechanism he also did early work on scientometrics and the Japanese atomic bomb effort. He finally published his analysis in “Gears from the Greeks” in 1974, this included a detailed description of how the mechanism might have operated based on the gearing made visible by x-ray imaging.

The next attempt at a reconstruction was made by Michael Wright, originally curator of the engineering collection at the Science Museum in work starting in the early 1980s. He was joined by Allan G Bromley, a computer scientist and historian who was also involved in the reconstruction of the the Babbage. They quickly realised that Price’s theoretical reconstruction was in places somewhat creative. Wright ultimately produced a physical reconstruction of the mechanism over a period of 20 or so years.

Most recently, commencing in around 1998) there has been a collaboration led by Mike Edmunds at Cardiff University (The Antikythera Mechanism Research Project). They were able to bring to bear better x-ray tomography which was even able to reveal the details of inscriptions inside the accreted masses of the mechanism fragments, alongside Polynomial Texture Mapping, a photographic technique utilising multiple lighting angles and reconstruction to provide maximum information from surface markings. With collaborators at the Athens Nation Museum they also had access to an additional major fragment which had recently been discovered. Their work was published in the journal Nature (here in 2006 and here in 2008).

The comparison between the Wright and Edmunds collaborations is intriguing, in terms of scientific prestige the Edmunds collaboration have published on the mechanism in Nature the premier general science journal. They are a large collaboration with the best equipment, and fit well within the conventional scientific context. Wright, and to a lesser extent Bromley, were different. Wright in particular comes over has being very hard done by in the process, working in his spare time on the mechanism, always apparently “junior” to Bromley (the formal academic) and ultimately being pipped to glory by the Edmunds collaboration. His story comes through because Marchant has clearly interviewed many of the participants, rather than relying on the published literature. From the point of view of the published literature, all that is really visible to the scientific world, Wright’s efforts were virtually invisible until long after he had started work on the Mechanism.

The “problem” for the earliest interpreters of the mechanism is that it was so utterly different from anything else available from the period. There were no other clockwork like devices and few mentions of them, indeed the next instances were thought to be around 1000AD – it looks like the Antikythera Mechanism was dropped into the past from elsewhere. Nowadays it can be seen that this isn’t true. Archimedes and Ctesibius had been making complex mechanical devices in the 3rd century BC, although there are no physical remnants and the written records are sparse. On the other side, mechanisms of this type were in existence through to 1000AD and from then clocks appeared very rapidly suggesting a pre-existing store of knowledge.

In ancient Greece it is believed there were hundreds of thousands of bronze statues, the number left today are in the hundreds, at most. What chance even a few hundred rather unassuming objects to survive? As for the written record, what survives from the period has been repeatedly transcribed to suit the prevailing conditions, and they did not seek detailed descriptions of recondite mechanics. Can you lay your hands on the blue prints for an NMR machine?

The Antikythera Mechanism would have been made on the basis of the astronomical observations of the Babylonians who preceded its Greek makers. They had no “mechanical” model of the motions of the stars but they had a long, deep observational record of their movements. I’m interested in the night sky, and I can’t tell you but the details of the phases of the moon, even where it rises and sets let alone the motions of other planets are a mystery to me in the intuitive sense (I know I can look them up). The ancients had little to do at night, other than look at the sky – I feel I’ve lost something through having so many distractions and a night sky obscured by light pollution.

Footnotes

My Evernote on the book contains page by page comments, and also some links to related material

Mar 02 2012

Book Review: The Etymologicon by Mark Forsyth

The Etymologicon by Mark Forsyth

The Etymologicon by Mark Forsyth

“The Etymologicon” by Mark Forsyth is a book of the origin of words, of their etymology. It’s based on the author’s blog, the Inky Fool, it reads very much as a sequence of blog posts strung together. This isn’t necessarily bad but does sometime make it feel like a a unrelenting, whirlwind tour of the origins of English words.

Although English was never my strongest subject at school this combination of history and language has always fascinated me. I thought I’d pluck out and summarise a few little gems that caught my eye:

Romany people have received a range of names, based on the mistaken assumptions of their origins. The term “gypsy” arises from those that thought they came from Egypt, most bizarrely the Spanish at one point seemed to believe they come from Flemish Belgium, hence the word “Flamenco”. The Roma ultimately come from India, their language having its roots in Hindi and Sanskrit.

Wamblecropt, meaning “afflicted by nausea” appeared in Cawdrey’s Table Alphabetical of 1604 which Forsyth cites as the first dictionary not directed to the aid of translators. He also highlights that the fame of Dr Johnson’s dictionary is not in its novelty as a type of book but in Johnson’s fame as a learned man. I feel there is a need to randomly reintroduce such words to the language, to see if their time has returned. “I am often wamblecropt on the train into work”.

I’d always assumed that Nazi was a a contraction of Nationalsozialistiche Deutsche Arbeitpartei, which it is but it was also a pre-existing term of abuse relating to Bavarian peasants who were the butt of jokes in Germany in the early 20th century. Nazi is a contraction of Ignatius, a common Bavarian name.

“Terrorism”, it seems was coined in English after the French Revolution to describe a system of government based on terror.

Rather romantically, the ring finger is so-named because early medicine held that the ring finger was directly connected to the heart and could be treated as a proxy for the treatment of heart problems, and so when we marry we put a ring on our ring finger. My wedding ring is the only jewellery I wear. Somewhat insensitively, when choosing a ring for Mrs SomeBeans at which point the issue of a ring for me was first raised, I exclaimed that I wasn’t particularly interested if it cost as much as hers did. I relented fairly soon afterwards, having saved on an engagement ring which Mrs SomeBeans wouldn’t have been able to wear as at the time she worked in the food industry.

You’ll be pleased to know that there was a “gorm” to go with “gormless”, gorm was a 12th century Scandinavian word meaning sense or understanding. Similarly, there were once also “feck” and “reck”, now only found in “feckless” and “reckless”. Happily there was also a “gruntle”, which is now only found in “disgruntled”. To gruntle is to grunt often, as pigs might do, in this instance dis- prefix is an intensifier.

Obviously I could go on, but it would be repetitive.

It’s difficult to know with a book like this the level of referencing which is desirable, it is light on references but the author acknowledges this at the end of the book, providing a brief bibliography and some more detailed references as an example.

Books similar to this include, Lynne Truss’s “Eats, shoots and leaves” and David Crystal’s “The Cambridge Encyclopedia of The English Language“. The most useful part of my library membership is online access to the Oxford English Dictionary, which is also a goldmine for etymologists.

All in all an entertaining read, and compatible with the stresses of new parenthood.