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Winning in Vietnam

Robert Asprey's monumental work on guerilla warfare, War in the Shadows, is really about the Vietnam War, even as he ranges across the centuries in his analysis of asymmetric methods in war. He reserves his most exacting rhetoric, and his greatest scorn, for those who ordered and conducted the failed American invasion of Indochina, for their amorality and incompetence. I was struck by how often, through the years from 1945 onwards, he was able to quote a general who confidently announced impending victory or at least great strides towards it. So I collected a few.

Source

Robert Asprey, War in the Shadows (Macdonald & Jane: 1975)

Background

We start in 1945 with British and French troops in south Vietnam, along with the defeated Japanese army.

Under the terms of the Potsdam Conference as confirmed at Yalta, Britain and China shared responsibility for occupying Vietnam: British forces moving in south and Chinese …

Bengal: saltpetre

A seventeenth-century army increasingly relied on gunpowder, and the production of that vital resource required three mineral ingredients - charcoal, sulphur and saltpetre. Of these, the two minority ingredients were charcoal, which could be obtained readily wherever there were trees, and sulphur, which was mined in many places and was fairly cheap. However, three-quarters or so of the mix was taken up by saltpetre, the mineral potassium nitrate. Saltpetre forms naturally in small quantities in some locations, but for regular supply it had to be 'farmed' by heaping animal dung with earth in large beds that were then treated with urine for a period of months. Bacterial action produces potassium nitrate, which with the right technique can be refined to a relatively pure crystalline product.

The Mughal army was as gunpowder-based as the European armies. At the start of the sixteenth century the technologies were very similar, with European powers making …

Year 1688

The so-called 'Glorious Revolution' in England in 1688 was a pivotal event in the country's history. It also began a train of events leading to almost twenty years of war in Europe and the emergence of Britain as a major power. This is why elsewhere I cover the life of Thomas Pitt who, living from 1653 to 1726, straddled this period of rapid social and economic change in Europe and the world.

Wills, 1688: a global history

To take an overview of the deepening connections between parts of the world, I will often go back to a short but highly interesting book, John Wills' global history of the year 1688. He speculates that: In 1688 a full sense of the variety of the world's places and peoples, of their separations and their connections, was confined to a few, referring to the small number of travellers as well as the literate …

Transmission of mathematical ideas

A few notes here from G.G.Joseph's excellent book, The Crest of the Peacock, specifically looking at evidence for transmission of mathematical knowledge and number systems.

Babylonian origins

See p.111 for first example of Diophantine technique used by Babylonians.

The second example is a cuneiform tablet, catalogued as Plimpton 322. It is not a trigonometrical table but is evidence for the methodical production of Pythagorean triples. We are all familiar with the (3,4,5) triangle and its properties, (that 3²+4²=5²), but not everybody will be aware that there are many more such combinations, infinitely many in fact. They are known as Pythagorean triples. Examples include (7,24,25) and (96,110,146).

With the help of some fairly elementary algebra, it is possible to generate triples using a formula.

This method of generating integral Pythagorean triples is usually attributed to Diophantus (c …

Size of Earth and the Antipodes

In his thesis The origins of antipodal theory (see below for details), Schiöth gives a useful summary of the history of measuring the earth's size.

Calculating the size of the earth

The first known calculation in the extant literature of the circumference of the earth might be derived from Eudoxus. In On the Heavens (298b), Aristotle attributes the figure of 400,000 stades for the circumference of the earth, to unknown 'mathematicians.' Due to Eudoxus’s known influence on Aristotle’s astronomy, some scholars have pointed out that in this passage Aristotle might be referring to Eudoxus.

Value of the stade: The stade (στάδιον or stadion) was an ancient Greek unit of measurement, ‘in origin the distance covered by a plow in a single draft, consisted of 600 Greek feet; but the length of a foot was subject to some local variation in the Greek world’ (Harley & Woodard, 1987, p …