... not mine, an Ogden Nash quote.
This week's You're Dead To Me dealt with the Terracotta Army protecting the tomb of China's First Emperor, of whom the National Museums Liverpool write:
A life of conquest shaped the man who would become China’s First Emperor. Born Prince Ying Zheng, he was just 13 years old when he became King of the Qin State in 246 BC. Initially supported by his mother Queen Zhao Ji and chancellor Lü Buwei who effectively managed the government, the young king took full control of his kingdom aged 22. With massive armies he overpowered the six remaining independent kingdoms of the late Warring States Period and unified China in 221 BC; putting an end to centuries of political turmoil, constant war and endless bloodshed.
'Putting an end to ... bloodshed' is a matter of opinion. What he did was arrogate to himself the business of bloodshed. His mausoleum was not discovered until 1974, and the written history – including records of folk memory – does not mention the tomb with any specifics. This can only have been achieved by the deaths of all the thousands of unfortunates who toiled on that decades-long, 50 km2, building site (which shows evidence of deformity [caused by hard labour] and possibly torture...
<tangent type="etymological nazi">
I admit, without pride, that when the learned guest on the podcast mentioned "leg manacles" I felt a reflex twitch on the grounds that manacles restrict the movement of manus (Latin "hands") a silly and trivial objection, I know. This blog has mentioned "The Etymological Fallacy" many times.
<tangent>
...). The army was armed with bronze weapons, with cutting edges and interchangeable moving parts: if the trigger on one mannequin's crossbow broke, for example, it could be replaced off-the-shelf. This was not bad for the 3rd century BCE.
Meanwhile – that is, over two millennia later – an Englishman recognized the benfits of standardization.
Prior to the 1840s there was no universal standard for thread pitch - every manufacturer was left to their own devices. In a way, any screw pitch ...
<parenthesis>
This was a new usage to me. The best explanation I've found is a picture in the Manual of Engineering Drawing:
... you could make, you could use and no one would have grounds to complain. At the same time, the product designers of the time had no readily available standards to pull from or common choices to pick between.
Naturally this led to severe fragmentation and millions of incompatible screws, nuts, and bolts - each slightly different. Larger companies narrowed in and developed their own internal guidelines, but these lacked the reach and accessibility of a singular standard. That was the case until Joseph Whitworth took the stage in 1841....
Joseph Whitworth developed a screw thread design that was adopted by major English railroad companies and quickly spread across the country. His papers on screw threads exposed the “evils” of figuring out thread pitches without a uniform standard. While Whitworth admits that any standard would be based on largely arbitrary decisions, and there would always be special cases that don’t fit the standard, he cautions that there is more to be lost by delaying and urges the attention of engineers across the nation. With the support of the railroads, then the Royal Dockyards and shipping companies, Whitworth’s 55-degree thread... [held sway for a blissfully unchaotic 20-odd years].
That use of quotation marks about "evils" struck me at first as the sort often used by naive writers to denote emphasis. But in his paper addressed to the Institution of Civil Engineers in 1841, Whitworth did use the term "evil" (although there was only one, albeit a pretty heinous one – the "embarrassment" of specifying thread pitches that are not "a multiple or submultiple of the common inch measure":
The screw threads which form the subject of this paper are those of bolts and screws, used in fitting up steam engines and other machinery. Great inconvenience is found to arise from the variety of threads adopted by different manufacturers. The general provision for repairs is rendered at once expensive and imperfect. The difficulty of ascertaining the exact pitch of a particular thread, especially when it is not a multiple or submultiple of the common inch measure, occasions extreme embarrassment. This evil would be completely obviated by uniformity of system, the thread becoming constant for a given diameter.
). That's enough for now. I can't even give an unalloyed endorsement of You're Dead To Me; it's fun and informative, but I struggle to filter out the self-congratulatory sniggering of the presenter.
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