Category: Book Reviews

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

Book review: Crypt by Professor Alice Roberts

My next review is for Crypt by Professor Alice Roberts, this is one of a sequence of three books on archaeology and history centred around burials. I reviewed Ancestors a couple of years ago which covered the prehistoric period. Crypt covers the second millennium of the current era, the third book, Buried, covers the first millennium and is on my reading list.

In common with Ancestors, Crypt considers seven burials across a period of time – in this case the medieval period – from about 1000CE to 1500CE. The burials are a launch point for a wider discussion covering archaeology, genetics, disease pathology and history. It is the study of DNA from ancient bodies that has been the biggest innovation over the last 25 or so years, and it has been applied to a lot of existing archaeological collections as well as new digs. It can show how diseases have emerged and evolved over the period of human history.

“Crypt” is not a particularly accurate description of the burial sites, the chapters look at a mass grave in Oxford (in a ditch) whose members met violent ends, a leper colony near Winchester, Thomas Beckett’s (possible) burial at Canterbury Cathedral, burials at Norton Priory near Runcorn showing evidence of Paget’s disease, plague pits and evidence for the Black Death, the Mary Rose and the skeletons of otherwise healthy men, finishing with a burial at a church in York and syphilis.

In contrast to Ancestors this book has much more historical material, understandably since Ancestors covered prehistoric burials.

The book starts with the discovery of 35 skeletons in a ditch in Oxford, primarily young men who had met a violent end. Ultimately this was linked to Æthelred the Unready’s edict to kill Danes in England dated to 1002CE in the Anglo-Saxon Chronicles. Although the carbon dating initially indicated the skeletons were from a slightly earlier period, isotope analysis suggested they had a diet very high in fish, which is know to lead to systematically older carbon dating. It also suggest that the skeletons may have belonged to Danes, whose economy was very dependent on fishing. Contemporary reporting of the massacre was limited but picked up after the Norman invasion as some sort of justification for the invasion.

Leprosy was spreading in the 11th century – possibly as a result of the Crusades. The second chapter of Crypt concerns the hospital on Magdalene Hill on the outskirts of Winchester. 100 graves were excavated of which 85% had inhabitants afflicted by leprosy – this is very clear from skeletal evidence. The hospital was founded around 1000CE, in this period hospitals were starting to be founded but the line between hospital and monastery/abbey was blurred. In the modern era PCR analysis has shown that many have leprosy without symptoms.

In some senses the chapter on Thomas Beckett is anomalous, it is almost entirely historical. On his well-documented death he was quickly made a saint and his tomb at Canterbury Cathedral, featuring a special alcove for his severed scalp, became a site of pilgrimage. The archaeological interest is because none of the tomb of St Thomas remains, it was removed by Henry VIII during the Dissolution who also comprehensively clamped down on celebration of St Thomas. The chapter also talks about the politics between the local royalty and the Roman church.

The chapter on Norton Priory, near Runcorn, brings things home for me – I live just down the road in Chester. The new visitor centre looks rather fine. The focus here is on Paget’s Disease which is a disorder of the bone which is more common in north west England, and used to be more common generally. As a disease it is still a bit of a mystery. Norton Priory has a very high incidence of Paget’s in its graveyard – as many as 3 in 20 skeletons show evidence of the disease.

Paget’s disease and leprosy both show clear signs of disease on the bone, the Black Death on the other hand, does not since it kills its victims in days, or even hours giving little time for bone to be affected. This means that genetic methods are used to diagnose the disease in ancient remains. They were first applied to the Black Death around 2000 but the results were disputed with the identity of the disease micro-organism for the Black Death only confirmed as Yersinia pestis in 2011. It has been identified in victims of the earlier Justinian plague.

For Roberts the Mary Rose is a significant part of her childhood memories, as it is for me – many of us around the age of 50 will remember the raising of the Mary Rose shown on an old CRT TV in the school assembly hall. The interest in the Mary Rose is that the anaerobic silt of the Solent preserved the skeletons of its crew very well and nets to prevent boarders meant many men were trapped on the sinking ship. The primary interest here is in counting the dead, best estimates are rather below the historical figures suggesting that the ship may have been under-crewed. The skeletal pathologies are also of interest – what was the impact of the types of activities that sailors and fighting men undertook on their skeletons.? The Mary Rose is also the home of a large cache, over 100, of English long bows – very few of these famous weapons have been preserved – in fact the Wikipedia article cites only three other examples not from the Mary Rose.

Crypt finishes with an unusual burial in a York church, (All Saints on Fishergate) and syphilis. The burial is unusual because it is a pit burial in the apse of the church. The buried skeleton contains crater-like lesions characteristic of advanced syphilis. The origin of syphilis is still a mystery, there has long been a “Columbian Hypothesis” that Columbus brought syphilis back from the New World (in exchange for a wide range of diseases brought from the Old World) – however genetic analysis has failed to find the syphilis bacteria in remains prior to 1492 in either the New or Old World. The burial is thought to have been of an anchoress, possibly Lady Isabella Germann, buried around 1493.

The disease pathology sections are interesting but can be quite lengthy, I noticed this particularly in the chapter on the skeletons of the Mary Rose in the discussion on the skeletal features arising from archery – it all became clear when Roberts writes of this topic “…this had formed the backbone of my PhD”!

Reading this book it becomes clear that the various diseases mentioned, leprosy, syphilis, and Black Death went through periods of high prevalence across human history -this is covered in Peter Frankopan’s book The Earth Transformed. The bubonic plague – the disease responsible for the Black Death, is covered in Simon Schama’s book, Foreign Bodies, at least for the 19th century outbreak.

I enjoyed this book, so much so that I have just bought the last (for me) of the sequence.

Book review: An Immense World by Ed Yong

My next review is of An Immense World by Ed Yong, subtitled How Animal Senses Reveal the Hidden Realms Around Us. I reviewed Yong’s previous book, I Contain Multitudes a while back. Somewhat foolishly I was slightly reluctant to pick this one up since I felt I was clued up on the “five senses”. I was incredibly wrong about this quick judgement. First of all, “five senses” are a human-centric view promulgated by the ancient Greeks, secondly it turns out we have been learning a lot about animal senses in my lifetime and show no signs of letting up.

The book is divided into 12 reasonably long chapters, treating smells and tastes, light, colour, pain, heat, contact and flow, surface vibrations, sound, echoes, electric fields, and magnetic fields. Finishing with a chapter on how senses work together and one on the pollution of the senses in the natural environment with artificial light and sound. We can see here the traces of the original five senses but some are split (light and colour, sound and echoes), taste and smell are merged; magnetic fields and electric fields are new introductions.

A key concept which is found throughout the book is the idea of “umwelt”, the perceptual world of an organism, which was coined by Jakob von Uexküll in 1909. Touching on the penultimate chapter first, this “umwelt” is almost impossible for us to fully appreciate – we can’t even be sure how the senses we share are experienced by other animals. Let alone how they work together with other senses that we don’t have.

One comfort of this book is that it turns out that human senses are not that bad. Yong cautions though that absolute comparisons across species are often wrong, and don’t account for large variations between individuals. His goal is to talk about diversity rather than ranking. A general theme is that although some animals might exceed us in terms of acuity, often it is the speed at which a response can be made that is the critical factor.

All of the chapters involve Yong talking to scientists, not just about the science but how and where it is done, which is engaging.

For smell the key ability that animals have over humans is better sampling so that scent traces can be followed, snakes do this with their forked tongues whilst dogs do so with subtly designed airways. I was also interested to learn that sea birds are sensitive to dimethyl sulphoxide which is an indicator for a bountiful ocean, and whose concentration likely serves as a large scale map. Taste is covered in just a couple of pages, essentially it is used by animals as a final go/no go decision on eating stuff – smell is a much more subtle sense.

It turns out human vision is pretty good compared to other animals, at least in certain aspects. Only eagles and other raptors have better acuity, certain flies have vision which is up to 10 times faster than ours. Many animals can sense light outside the human visual range, in the ultra-violet and infra-red and use this ability for specific purposes. I think the key takeaway for me was that the human visual system is not a blueprint for all visual systems, mantis shrimps, for example have a ridiculous number of different types visual receptors but they are used in a very different way to ours – almost like a set of special purpose triggers for motion, colour, light direction rather then general receptors whose signals are processed by the brain. It also seems that the colour vision is just not that important for survival – many people get by with impaired colour vision, and although colour vision like ours is not rare amongst certain groups it is in no way necessary for survival.

Yong makes a point about how our own senses guide our view of the mental world of other animals, we see cows as passive because they are not always looking around at their environment, as we do but they have virtually panoramic vision so they don’t need to constantly move their heads to see what is going on around them.

The chapter on pain starts with the naked mole-rat, whose tolerance of very high levels of carbon dioxide in their burrows is enabled by their limited ability to sense the pain induced by acidic substances (carbon dioxide forms carbonic acid). Much of pain research seems to be about belatedly realising that all manner of animals feel pain, and perhaps we shouldn’t inflict it.

Heat is generally detected by the TRP channel proteins, with different variants responsible for for different temperatures including “dangerously hot” and “dangerously cold” the temperature at which they are triggered varies from animal to animal. Melanophila (fire) beetles have incredibly sensitive heat sensing organs that can detect fires by their infra-red emissions from miles away. Similarly snakes are able to detect the direction heat is coming from, with signals processed alongside sight.

It turns out that touch is quite a varied sense, we think in terms of our fingers touching solid surfaces but for many animals the feel of flow in water is more important. The feeling of flow of water helps predators catch their prey, and fish to school together. Related is sensitivity to surface vibrations, which insects and other invertebrates have developed to an incredible degree. The songs of certain insects in surface vibrations are as sophisticated as bird song.

My favourite fact from the chapter on sound is that owls have one ear higher than the other so that they can locate sounds vertical by arrival time. I also learned that zebrafinches have very high sensitivity to the fine structure of their songs but are less sensitive to the notes they sing, it made me think a little of “tone” in guitar playing.

We should see echolocation as touching with sound, it wasn’t until the 1930s that it was appreciated that bats echolocated, and rather later for dolphins. Echolocation can be remarkably sensitive, dolphins can not only identify different materials from echolocations but they can match an object “seen” with echolocation to one “seen” with their eyes. Military interest in echolocation is essentially a result of a recognition that human technology lags biology.

Another novel sense, as far as humans are concerned, is electric. It has long been known that some fish used electricity as a weapon, but only in the 1950s was it recognised that it was also used for sensing. There are two types of electrosensing, one is active – like echolocation but it is omnidirectional and there is no wait for a signal return. The second is passive, some animals can detect the weak electric fields of animals going about their normal business. In common with echolocation the animals that use it have exquisite control over the frequencies, and sequences, of the probe pulses they generate.

Sensitivity to magnetic fields is the most elusive of senses, it has only been recognised relatively recently and we still don’t know for sure exactly how animals are sensitive to magnetic fields – there has been no conclusive identification of the receptor cells.

Astronomers have long been concerned with light pollution but it has only been more recently that biologists have realised it is a significant threat to animals. Similarly with sound, we are sensitive to noise pollution close up but don’t appreciate the significant noise pollution in pristine-looking environments.

I thoroughly enjoyed this book, as I did I Contain Multitudes. The style is engaging, and the subject matter is fascinating.

Book review: A Philosophy of Software Design by John Ousterhout

Next for review is A Philosophy of Software Design by John Ousterhout. This a book about a big idea for software design. The big idea is that good software design is about managing complexity. In Ousterhout’s view complexity leads to a set of bad things: (1) change amplification – small changes in code lead to big effects, (2) cognitive load – complex software is difficult to understand, and (3) unknown unknowns – complex software can spring the unexpected on us.

Ousterhout covers this big idea in 20 short chapters with frequent reference to a projects that he has run with students repeatedly (including a GUI text editor and a HTTP server) – providing a testbed for reviewing many design choices. He also uses the RAMCloud project as an example, as well as features of Java and the UNIX operating system. This makes a refreshing change from artificial examples.

To decrease complexity requires developers to think strategically rather than tactically which goes against the flow of some development methodologies. Ousterhout suggests spending 10-20% of time on strategic thinking – this will pay off in the long term. He cites Facebook as a company who worked tactically and Google and VMWare as companies who worked more strategically.

At the core of reducing complexity is the idea of “deep modules”, that’s to say systems that have a relatively small interface (the width) which hides information about a potentially complex process (the depth). The Java garbage collector is the limiting case for this – having no user accessible interface. The aim of the deep modules is to hide implementation details (information) from users whilst presenting an interface that only takes what is required. This means deciding what matters to the user – and the best answer is as little as possible.

This goes somewhat against the ideas of the Agile development movement, as expressed in Clean Code by Robert C. Martin (which I read 10 years ago) – who was a big fan of very short functions. I noticed in my review Clean Code that I have some sympathy with Ousterhout’s view – small functions introduce a complexity overhead in function definitions.

Also on the theme of Agile development, Martin (in Clean Code) sees comments as a failing whilst Ousterhout is a fan of comments, covering them in four chapters. I recently worked on a project where the coding style was to rigorously exclude comments which I found unhelpful, that said I look at my code now and see orphaned comments – no longer accurate or relevant. The first of Ousterhout’s chapters on comments talks about four excuses to not provide comments, and his response to them:

  1. Good code is self-documenting – some things cannot be said in code (like motivations and quirks)
  2. I don’t have time to document – 10% of time on comments will pay off in future
  3. Comments get out of date and are misleading – see later chapter
  4. The comments I have seen are useless – do better!

The later chapters focus on the considered use of comments – thinking about where and what to comment rather than sprinkling comments around at a whim. The use of auto-documentation systems (like Sphinx for Python) is a large part of realising this since they force you to follow standard formats for comments – typically after the first line of a function definition. Comments on implementation details should be found through the body of a function (and definitely not in source control commit messages). He also introduces the idea of a central file for recording design decisions that don’t fit naturally into the code. I include the chapter on “Choosing names” under “comments” – Ousterhout observes that if you are struggling to find a good name for something there is a good chance that what you are trying to name is complex and needs simplification.

Certain types of code, Ousterhout cites event-driven programming, are not amenable to producing easy to understand code. He also dedicates a chapter to handling errors – arguing that errors should be defined out of existence (for example deleting a file that doesn’t exist shouldn’t cause an error, because the definition of such a function should be “make sure a file does not exist” rather than “delete a file”). Any remaining exceptions should be handled in one place, as far as possible.

There is a chapter on modern software development ideas and where they fit, or don’t, with the central theme. Object-orientation he sees as good in general, with information hidden inside classes but warns against over use of inheritance which leads to complexity (just where is this method defined?). He also comments that although design patterns are generally good their over-application is bad. He is in favour of unit tests but not test-driven development. This seems to be related to his central issue around Agile development – it encourages tactical coding in an effort to produce features rapidly (per sprint). He believes Agile can work if the “features” developed in sprints are replaced with “abstractions”. He doesn’t like Java’s getters and setters, nor its complex serialisation system which requires you to setup up buffering separately from opening a file as a stream – I remember finding this puzzling.

I enjoyed this book – it provides some support for continuing to do things I currently do although they are a little against the flow of Agile development and food for thought in improving further.

Book review: Her Space, Her Time by Shohini Ghose

My next review is of Her Space, Her Time by Shohini Ghose. I picked this book up as a result of a review in New Scientist. It is in the spirit of Broad Band which covered the contributions of women to computing over the years – contributions which have historically been ignored. Her Space, Her Time does the same for women in physics, generally on the astrophysics and cosmology side of the subject.

The book is divided into seven chapters each covering an area of physics and a group of women who worked in those areas. The chapters cover star cataloguing (and rather more), the big bang, the space programme, radioactivity, nuclear fission, particle physics and dark matter/ beta decay. This results in a coverage which is approximately chronological.

There are some recurring themes in the book: women not allowed entry to universities for undergraduate and graduate studies, women not allowed employment in university departments and facilities (often the pretext is the lack of toilets for women), women not allowed employment at the same institution as their spouse (this seemed common in the US and its effect on the recruitment and promotion of women was noted as far back as 1966), being ignored by the Nobel Prize committee and (sometimes) their male collaborators. These women were frequently the only women in the room. Fleeing Nazi Germany (and Austria) is a theme too but that applies equally to men.

On a more positive note their work was often recognised and rewarded during their lifetimes by their scientific communities. In at least the case of Ernest Rutherford and Ernest Lawrence they had the support of senior scientists throughout their lives.

The Harvard Observatory features heavily in the first couple of chapters. Women originally became involved as “computers” analysing the stars in the photographic plates. They included Williamina Fleming, Annie Jump Cannon, Antonia Maury and Cecilia Payne-Gaposchkin with Anna Draper providing funding to the observatory via a bequest in the late 19th century. In they first instance they were analysing stars for brightness and then later for spectral features. A group of women were responsible for compiling the “Harvard” stellar classification scheme which classifies stars by temperature using the letters O, B, A, F, G, K, M (typically remembered by a sexist mnemonic). One of the women, Henrietta Swan Leavitt, discovered the relationship between brightness and period for stars which is central to measuring intergalactic (and shorter distances) and was key to understanding the scale of the galaxy and the universe. Over a very long period Harvard Observatory allowed women to be employed as astronomers, and finally become professors in astronomy. The transitions usually being the result of a change in observatory or university management.

The third chapter is a bit of an oddity, looking at women’s contributions to the space programme on the project management and rocketry side of things rather than physics as such.

The final four chapters are then an extended collection on nuclear physics starting with Marie Skłodowska-Curie, and the less well known Harriet Brooks who worked on the new subject of radioactivity in the late 19th century. Brooks worked with Rutherford, publishing in 1904 in Nature on their discovery of radon. Rutherford and Frederick Soddy would earn the Nobel Prize for the transmutation of elements whilst Brooks was left out. Rutherford and Brooks clearly had a long personal relationship, ending in 1933 on her death at the age of 56. Brooks had left physics research in 1907 when she married Frank Pitcher.

Chapter 5 largely concerns Lise Meitner who was involved in the discovery of nuclear fission with Otto Hahn with whom she worked closely for many years. Hahn received the Nobel Prize for their work on nuclear fission, whilst she did not – this has been seen as one of the more egregious omissions of the Nobel Prize Committee – Meitner was nominated for a Nobel Prize 48 times and was widely recognised as an expert in her field. Her position was made more difficult because she was Jewish, worked in Austria and with Hahn who despite protestations was a Nazi sympathiser at the very least.

Chapter 6 concerns cosmic rays and the photographic detection thereof. It starts with Bibha Chowdhuri who is from Ghose’s home city of Kolkata and was later to discover cosmic ray muons using this method. The focus of the chapter though is Marietta Blau and her student Hertha Wambacher who developed the method of photographic detection of cosmic rays. The Meitner/Hahn story is reprised here with Jewish Blau forced to leave Vienna in 1938 with her student Wambacher, a Nazi sympathiser, remaining to take credit. Elisa Frota-Pessoa, a Brazilian physicist, is mentioned somewhat incidentally towards the end of the chapter with Ghose stumbling on one of her (very prescient) publications whilst researching other work.

The book finishes with the slightly odd pairing of Wu Chien Shiung who was instrumental in the discovery of parity violation which won her colleagues Tsung-Dao Lee and Chen-Ning Yang the 1957 Nobel Prize in Physics (they specifically mentioned her in their acceptance speech) and Vera Rubin who is credited with discovering dark matter by measuring the rotation curves of galaxies and observing that they flatten at large radii – an indicator of the presence of extra, unseen matter.

Reading back through my notes, women were at the heart of modern physics through the 20th century, often those women were the only ones in the room – it is clear they were exceedingly capable. The men around them collected a dozen Nobel Prizes whilst the only woman from this book to win the Nobel Prize for Physics was Marie Skłodowska-Curie. Maria Goeppert Mayer shared the Nobel Prize for Physics in 1963 she is the only other woman to win in the 20th century. She is not included in this book, perhaps because her Nobel Prize meant she was already well known.

In the past I thought the Nobel Prize committee were simply a bit careless in failing to award women but reading this book it seems they were rather purposeful – the physics community knew these women, and the significance of what they had done, and many were nominated for a Nobel Prize, often repeatedly.

As a result of this book I am now interested in a parallel volume of Indian scientists in the West!

Book Review: Grace Hopper – Admiral of the Cyber Sea by Kathleen Broome Williams

After reading Broad Band by Claire L. Evans, about women in computing, I realised Grace Hopper was important, so I thought I’d hunt out a biography. I found Grace Hopper: Admiral of the Cyber Sea by Kathleen Broome Williams. Unusually I bought it second hand – my copy came from the Richard Stockton College of New Jersey Library Pomona, and has an austere, maroon cover.

Grace Hopper was born in New York City in 1906, she died in 1992. An undergraduate in mathematics she started a career in teaching at Vassar College but joined the Navy after the US joined the Second World War. She was posted to work on the Mark I computer at Harvard. She subsequently wrote the first software compiler, and was instrumental in the creation of the COBOL programming language. After “retiring” she then had a long career in the US Navy working on standardising their computing systems. After finally retiring from the Navy she worked for DEC for a few years until her death at the age of 86. She finished her career a rear admiral in the US Navy and has a battleship named for her (the USS Hopper) amongst numerous other rewards.

Grace Hopper gives some feel as to how it was to grow up in a relatively wealthy New York City family. The Hopper family had a holiday home in Wolfeboro, New Hampshire which, when she was small, was a day and a half travel to reach from New York City. She was brought up to be self-sufficient and trained in mathematics. Her father worked in insurance and was a double amputee – he wanted to make sure his children could fend for themselves should he die although he survived to a fair age.

Hopper studied mathematics first at Vasser College before going to Yale for a PhD in mathematics. She married Vincent Hopper in 1930, they bought a summer home of their own in Wolfeboro for $450 – part of a wedding gift. They were divorced in 1941 although it was not something she talked about, despite giving numerous interviews later in her live. Grace Hopper does not indicate the grounds for her divorce. After gaining her degree she became a lecturer in Vasser College where she was an excellent and committed teacher.

When America joined the war she was keen to serve in the US Navy which she achieved following some struggle. Fundamentally they were not keen to employ women, furthermore she was older than the Navy typically recruited, technically underweight and in a reserved occupation (as a lecturer in mathematics). Eventually she joined in 1942, and finally entered service in 1944, after training. She was proud to work in the Navy throughout her life and even whilst employed in industry she continued in the reserve service. In her Navy service she found a link with the dignitaries, including royalty, she met in later life.

Her naval placement was with the Mark I computer at Harvard, invented by Howard Aiken and built by IBM. It was the first programmable electromechanical computer in the world. Based on the slightly older relay technology rather than valves found in successors it was used principally for ballistic calculations as well as calculations of various function tables. Aiken was pretty tough to work with but Hopper clearly knew how to handle him and held him in high regard. She worked on many of the Mark I’s smaller programming jobs as well as doing more than her share of documentation and report writing.

One issue with the Mark I was that it was programmed with paper tape, the programs and data are stored as a pattern of holes 3-4mm across punched out the tape. There was a lot of paper around, as well as the disks of paper punched out from the tape. Sometimes one of the punched out disks was re-united with a hole causing an error, as Hopper pointed out “a hole getting back into a hole”!

After the war it was clear she would not be able to continue at Harvard, so she let to work on the UNIVAC at the Eckert–Mauchly Computer Corporation, later bought by the Rand Corporation and then IBM. Through Hopper’s life we see the birth and maturing of the new computing industry.

Hopper realised there was a need for standardisation in programming languages. There were an increasing number of different types of computer around, and the maintenance and programming of such computers was a bigger job than had initially been realised. Standardisation reduces this problem because a program written for one computer can be run on another. This is how COBOL was born, the Navy sponsored the Committee on Data Systems Languages (CODASYL) which created the COBOL programming language which was derived from Hopper’s FLOW-MATIC language developed for the UNIVAC.

As a scientist and software developer for 30 years I was scarcely aware of COBOL, yet it comprised approximately 80% of running code in the late nineties, according to Gartner. I imagine that figure has not dropped greatly. There is clearly a huge body of COBOL “dark matter” that software developers don’t talk about. The reason for COBOL’s obscurity seems to be the disdain of the academic computer science community, FORTRAN – born at the same time – suffers a similar disdain.

During her time working on UNIVAC Hopper maintained her Navy connection through a reserve position, and in 1966 – at the age of 60 – she retired from the reserve to work full time for the Navy at the Pentagon. She continued to work in the Navy until 1986 when she left to join DEC, at the age of 80!

In this book Grace Hopper comes out as an exceptional character. Her great skills were rooted in teaching, the drive to build a compiler was partly making her own life easier but also democratising the process of programming. She also saw the importance of raising a generation of programmers. She was very personable but seemed to have virtually no personal life. She drank moderately and smoked heavily for most of her life, and clearly had a bit of a hording problem towards the end. She was a life-long Republican and saw little value in the women’s rights movement – her own enormous success giving her the impression that there was no inequality to address.

Throughout her life, well into the period others might consider retiring, she was was engaged in a full schedule of public speaking. She gained many rewards, and a great deal of recognition in her lifetime.

I really enjoyed this book, the only place my interest lessened slightly was in the chapter describing administrative reorganisations of the US Navy. I am in awe of the achievements of Grace Hopper.