Thursday, 23 August 2018

The Curta Mechanical Calculator

And now for something completely different.

There was a time, children, when computers didn’t exist. And when they did exist (hello, Colossus) but were far from commonplace. People getting telephones at home, or even, gasp, televisions were new and exciting events. The radio was made of wood, and rather more listened to (perhaps due to the absence of TV, or because the people had better accents).

But what about calculators? Think of a calculator and you think of perhaps an app, or an electronic calculator, whether a simple everyday one or a swankier scientific version.

But what if those don’t exist? Well, you can work it out in your head.

Or you could use a mechanical calculator. The one pictured is the Curta, designed by Curt Herzstark. Born in 1902, he was an Austrian and son of a Jewish father. He’d completed the Curta’s design by 1938 but the Nazi annexation of Austria rather put the kibosh on production plans. He was ordered to make devices for the German army, until he was arrested in 1943 and sent to a concentration camp. Despite the less than ideal circumstances, Herzstark was able to redraw the designs from memory whilst in the concentration camp.

The mechanical calculator he created is similar in dimensions to a cylindrical deodorant can, albeit perhaps 2/3 the height and with a slightly larger diameter. It comes in an airtight two-part container.

I am not an engineer (the people who used the Curta perhaps the most), or a mathematician, but I must admit I found it to be not very intuitive (I’ve provided links to a few helpful Youtube videos at the end of this article). There is a series of movable switches running around the lower part of the cylinder. On the top is a handle that can be rotated either in the up or down position, with a separate ring that can be rotated (with the top part raised, this resets the device).

Turning the handle is curiously satisfying, like grinding a pepper mill full of numbers.

It turns out the switches on the lower part are for integers to add, subtract, multiply or divide. Turning the handle in the down position is for addition, in the raised position it subtracts. The number currently worked upon is indicated once an initial calculation (addition) has been made. So, the switches might be flipped to 1 0 2 4 at the bottom, the handle turned, and 1024 shows up on the top. A second turn adds the same again, yielding 2048. Multiplying small numbers is simply a matter of repeated additions.

For a larger multiplication, such as 2048 by 299, the upper part of the calculator is raised, and rotated so that the 2048 at the bottom (movable switches) is entered in the hundreds rather than units. This adds 204800 to 2048 (so, a multiplication by 101). Repeated twice is multiplication by 301. The top part is raised again and returned to the units, and the handle raised to the subtraction position. A double rotation removes 2048 twice, giving us 612352. As well as this, correct, answer, the multiplication factor (299) is shown on the upper part (in a silver rather than black area). [Experimentation reveals that if you subsequently alter the switches number, this is not taken account of. So, doubling to 4096 and adding once increases the count to 300].

Anyway, it’s an interesting little thingummyjig, and I thought people into engineering, history, or creative writing might be intrigued to learn about a calculator that doesn’t need any fancy electricity to get its business done.


Saturday, 18 August 2018

Review: A Brief History of Roman Britain, by Joan P Alcock

I found this book, which covers the entire period (and a little before) of Roman Britain to be rather interesting. It’s split into distinct halves, the former being a chronological account of Roman Britain (with a chapter on Celtic tribes beforehand) and the latter consisting of chapters focusing on individual topics, such as religion.

In that way it’s something of a mixture of Adrian Goldsworthy’s Fall of Carthage and Ian Mortimer’s Time Traveller mini-series.

The level of detail included is often very deep, particularly regarding food, and does help to put the reader in the shoes of, say, a 3rd century Briton, who might dislike the imported garum fish paste, love their new mosaic floor, and enjoy availing themselves of the public baths.

As the title indicates, the book is about Roman Britain, but to an extent it also functions as a microcosm of the rising and falling fate of the Western Empire more generally. Charting how the Empire won wars then won support from the Celtic leadership (and then lost it with greed and corruption, leading to Boudicca’s rebellion) is an interesting read but also functions as a template for how the Empire won over the people it had conquered. Similarly, declining resources partly due to increasingly frequent civil wars denuded the province(s) of military manpower, exposing them to barbarian attack and reducing economic activity as the well-paid soldiers left and suddenly merchants had lost a huge market. The benefits of city living through local bakers (removing the need to grind your own flour), baths et cetera was replaced by onerous burdens for local leaders (whose taxes and public duties increased as the Empire weakened), leading them to leave and reducing the urban population.

I was a little worried about the first chapter. It’s a little bit listy, not quite to the extent of The Iliad or the Bible, but thereafter the book’s much easier to read.

The writing style could be a little more fluid and little less matter of fact, but except for the first chapter on pre-Roman Celtic tribes, it’s a minor point.

There are one or two small errors that perhaps should’ve been caught. (I’m no longer a Grammar Nazi about this sort of thing, as some mistakes are almost certain in a full-sized book, but certain errors such as writing Julius rather than Julian can be a little confusing). There was also confusion over the name of Isis’ son (Hippocrates or Harpocrates, which might reflect a Greco-Roman divergence or simply be a homophonic typo).

However, those small quibbles apart, I found the book to be interesting, detailed (immensely so in some places), and enjoyable.


Thursday, 9 August 2018

Review: A History of the First World War, by BH Liddell Hart

A bit outside my usual area, but this military history seemed interesting, so I gave it a look. It charts the course of the war from beginning to end, including an introductory segment setting the scene.

Reminiscent of Dodge’s Napoleon biography (first volume), I actually found the political and military preamble to the war itself to be the most interesting part. Setting the scene with the Schlieffen plan and the varying states of readiness of the Great Powers was very nicely done.

The war was notable, amongst other things, for the rapid invention and development of new technology with battlefield implications. The radio, rail, aircraft, gas shells, and tanks were all either created for the first time, advanced swiftly or otherwise had great military significance. Machine guns had existed for a little while by this stage but this was the first war when they gave near total predominance to defence over attack (until the tank rolled up).

It was fascinating to read of how the Germans really could have won the war early on, but for Moltke buggering up the plan Schlieffen had put together some years earlier, denuding the powerful right of strength whilst reinforcing the centre.

I’ve read enough military history (admittedly, mostly classical) to know that some wars are notable for their brilliant strategy, and some are remarkable for surprising incompetence or plain bad luck. The latter was not unique to the First World War (we need only look for how the Romans repeatedly mishandled the Cimbri for evidence that strategic/tactical idiocy and generals infighting can endanger a national cause). World War One does have the slight mitigation that new technologies were not fully understood (aircraft could have been employed on a more aggressive basis, for example), and the exacerbating factor that the same mistakes were made repeatedly, at immense cost of human life.

The sheer numbers of people involved is also worthy of remark. Tens of thousands (or more) fell during the largest battles, millions of men lived in trenches.

I must admit I sometimes found things a little hard to follow, although the gist was never in doubt. (I maintain that military history is more interesting before the use of gunpowder became widespread). There is a good number of maps, with many chapters beginning with a map of the local situation. A nice addition, which was not present, would have been something along the lines of a trench cross-section or the odd diagram of a plane, machine gun or tank, but it would’ve been an extra rather than some necessary that is missing.

It should be firmly stressed that this is a military history, and politics, excepting the interesting preamble to war breaking out, is mentioned only in so far as it directly relates to the war. Russia vanishes after the revolution and peace is agreed between the Bolsheviks and Germany.

The author does comment on both military and moral failings of generals when it comes to mistakes made (some understandable, others perhaps less so), and also those of the ordinary soldier. Whilst rarer, instances of soldiers performing misdeeds (such as advancing well, then coming across quantities of alcohol and getting lashed as a ferret on Christmas Day) are mentioned. That said, the focus of the book is clearly on the military aspects, with morale (and morality) considered alongside ammunition, supply lines, and so forth as a military asset, or deficiency.

Overall, I found the book interesting, occasionally a bit tricky to follow. As I’ve said before, its sole interest is the military side of things, so those after something considering the political or social implications of the war will find it lacking. Those seeking to understand the strategic and tactical situation that unfolded from 1914 to 1918 will find it of significant use.


Thursday, 2 August 2018

Review: Game of Thrones, season six

It’s been a little while since I saw the fifth series of Game of Thrones, but I’ve got to say that the sixth was the televisual equivalent of fitting like a glove.

At this stage, and certainly by the end of the series, the TV show is ahead of the books, so if you’re waiting for the books then I’d advise you stop watching either at the end of the fourth or fifth series (the fifth is ahead of the books in at least one significant place but behind in many others). That said, there is some divergence between the media, so…

Naturally, there will be spoilers galore for the first five series. I shall keep spoilers of the sixth to the barest minimum reasonably possible. So if you want zero spoilers at all, stop reading now.


The three main prongs of the story are the ongoing power struggle in King’s Landing, the battle to rule the North, and Daenerys’ arc (which I shall not spoil but shall say is significantly better than the last few seasons of Meereen hum-drummery).

The High Sparrow’s storyline, the tale of insidious fanaticism, of the seemingly kind being amongst the most brutal (the benevolent dictatorship of stamping on your face, but only because it’s good for you) is absolutely fantastic.

The last two episodes, as is so often the case, were great, both wrapping up some storylines and promising future delights in others. The CGI remains very good but they aren’t over-egging it, using real actors, horses and practical effects well instead of simply relying on pixel magic all the time (and going for tiling of real images rather than making pretend ones where possible).

The general quality of acting is, as always, excellent. Jonathan Pryce as the High Sparrow deserves a special nod for his portrayal of the smiling, kind fanatic.

The story has one or two twists and turns that are predictable (one in particular is so lacking in surprise it did make me wonder how the unfortunate chap involved didn’t see it coming) but there’s a good share of cunning twists and fiendish plans. There’s a relatively strong focus on the three main plots I mentioned above.

Bran returns after an absence in the fifth series, and there are rather dramatic doings. He is not the only character to return (and I am not referring to he whom you might think I am referring to).

Downsides on the TV show itself are minimal. Dorne was a dog that didn’t bark, featuring but not nearly as heavily as I anticipated.

That said, keeping all the plates spinning with a show that has so many different threads is a difficult thing and, by and large, the showrunners have done a great job.

Weirdly, the case/packaging have changed a lot from the first five series, being significantly slimmer. I have mixed feelings as I don’t have that much room, but format changes within a series irk me.

As always, some commentaries are better than others. Sophie Turner and Kit Harrington (Sansa and Jon) were entertaining, and I enjoyed the quartet of chaps (particularly Dolorous Ed’s actor, Ben Crompton).

Whilst not a fan, as a rule, of behind the scenes stuff, the half hour (ish) look at the Paint Hall over 24 hours was quite fun because we get to see the cast and crew in their natural habitat. There’s also a behind the scenes look at a battle. Shan’t give details to avoid spoilers, but it was also pretty interesting.

By this stage, you pretty much know if you want to keep watching Game of Thrones or not. There are no clangers or woeful reasons not to watch, the general excellence is maintained, and if one or two plot twists are telegraphed, there are plenty more great moments to enjoy.