Sunday, January 14, 2018

On TV: Useful Engineering

Quite a while back, in 2011, I wrote a post called "More Junk Science on TV". Since then it's been the most viewed post on this blog, attracting tens of thousands of views, and sparking many comments right to the present day. Today I'm not writing about junk science; I'm writing about an alternative to it.

There's a popular tendency in the reactions to speak of "science" in relation to things that are not properly scientific problems; rather, they are matters of Engineering and/or Mathematics. The difference between these disciplines is not trivial, as I've had to reiterate time and again.

Rather than explain the difference at length here, let's let an engineer do it: this article on is called (conveniently enough), "The Difference Between Science and Engineering".

The difference is well described in this short quote by Henry Petroski:
Science is about knowing, engineering is about doing.
You do not need to know why or, often, even how something works to leverage the fact that it does work in order to successfully complete an engineering endeavour.

Likewise, Mathematics is not Science, not in the slightest. And let's let a mathematician explain that, as in this post entitled (equally conveniently): "The Difference between Science and Mathematics". Note that these are different differences. Mathematics is not Engineering either.

Some practical definitions:
  • Science is the process of gaining empirical knowledge by means of the Scientific Method: observation, hypothesis, refinement through further observation and experimentation, acceptance as a tentative law ("theory"), and repeat forever. Scientific statements cannot be proven. Rather, they can be supported or refuted by evidence.
  • Mathematics is process of manipulating values (whether they be spaces, as in Geometry, or abstract numbers) according to a set of axiomatic rules. The Scientific Method is not employed. All that's necessary is that the mathematical rules are rigorously self-consistent. Mathematical statements can be proven. That is, they can be shown to be incontrovertibly true within the applicable mathematical ruleset.
  • Engineering is the process of solving real-world problems. Engineers may employ Science and Mathematics as tools, but Engineering itself can be accomplished without explicit knowledge of these disciplines. The 'proof' of an engineering project is that it works.
Please remember this if you're ever tempted to use a phrase beginning with "Science cannot explain..." to object to what is clearly an engineering problem. While the Scientific Method can be employed to suss out the principles used to solve engineering problems, scientists are often not the best people to make the attempt precisely because their expertise is not in the area of practical application.

Also remember it if you're ever tempted to argue that knowledge of complex mathematics must have been available to an engineer without first demonstrating that the mathematical relationships found in an engineering work are not explained as a by-product of the process by which the work was accomplished. For instance, in any engineering work where a wheel (such as a hodometer) was used in measurement, a ratio of pi is not merely unsurprising... it is to be expected . In fact, such relationships are often good clues as to how something was built or how the work was planned. The engineer may readily recognize this even when a mathematician may get bogged down in analyses of the abstract relationships themselves.

  • Technology refers to the ways in which these disciplines, as well as skills, are combined and employed as a means of empowerment. Thus, a new technology may evolved from pre-existing scientific or engineering principles. For instance, the technology of baking bricks requires nothing that you did not previously develop for the making of sun-dried bricks and baking of bread. Technology is all about utilization. So it's inaccurate to say that the Ancients "lacked the technology" to accomplish certain feats using the 'primitive' tools available to them. Obviously they had the technology, because they accomplished the task. It's more accurate to say that we lack the technology to do so. Even though our knowledge of science, math, and engineering, taken separately, is vastly more developed and refined, we lack the skills... the knowledge of what specific combination of science, math, and engineering techniques were employed. 
The difference between these disciplines is profound. It's why we use the acronym 'STEM', and not 'S'.


With this in mind, I was very pleased to watch the History Channel series Ancient Impossible. Now, this originally aired in 2014, but I didn't see it then, possibly because I don't watch that much television. I found it on the History Channel website, and decided to try it out despite the title looking suspiciously like that of Ancient Aliens. I've rarely been so pleased to have been 'dissapointed'

Season 1, Episode 2, "Moving Mountains", touched on a few of the tasks deemed 'impossible' by my readers/commenters. This particular episode touched on the problems of breaking the defenses of Masada; moving water by means of aqueducts; and moving megalithic stones such as Egyptian obelisks and the stones of the retaining wall at the temple of Baalbek. In only one place does the presentation falter; and that's in depicting some dramatic tension as to whether a specific technique used in aqueduct construction would work. In practice, an engineer would only doubt the quality of his model. He would never entertain serious doubts as to whether an inverted siphon would work. Not only does Physics require it, but these things are commonplace. Several of these devices are present in every modern home. You probably call it a 'trap', and there's one under your sink. For that matter, the water pressure in your home is probably accomplished by means of a water tower, in which case, your whole water supply is delivered by means of inverted siphon.

But I was especially pleased that the episode reminded me of something that I should have passed on to my readers long ago... that being De Architectura, the engineering text written well over 2,000 years ago by the Roman engineer, Marcus Vitruvius Pollio ("Vitruvius").

Of particular interest is Book Ten, which deals with the constructions of machines. Vitruvius focused his effort to describing those things that are useful to engineers, as he deemed it unnecessary to describe those things (wheels, bellows, etc.) that were  that were common in a Roman's everyday life. His text isn't just descriptive; it's explanatory. That's a great thing for us, because it gives us a window into the mind of a Roman engineer, revealing how engineers looked at the world before Newton and the formal establishment of the Scientific Method. Here's what Vetruvius writes regarding the laws of mechanics (as translated by Joseph Gwilt, and available online):
The laws of mechanics are founded on those of nature, and are illustrated by studying the master-movements of the universe itself. For if we consider the sun, the moon and the five planets, we shall perceive, that if they were not duly poised in their orbits, we should neither have light on the earth, nor heat to mature its fruits. Our ancestors reasoned so on these motions, that they adopted nature as their model; and, led to an imitation of the divine institutions, invented machines necessary for the purposes of life. That these might be suitable to their different purposes, some were constructed with wheels, and were called machines; others were denominated organs [Dave's note: sometimes this is translated 'engines']. Those which were found most useful were gradually improved, by repeated experiments, by art, and by the laws which they instituted.
This should be largely familiar to us. Engineering is based on physical laws and is refined through practical application. Vitruvius differs from us mainly in mindset: whereas we think of a distinct separation between nature and artifice, the ancient engineer more explicitly thinks of machines as being the employment of those principles he has observed in nature.

That may sound like a subtle distinction, so let's phrase it a bit more crudely for effect: The modern engineer conquers Nature; the ancient engineer uses it. While this isn't completely accurate (technically speaking, all of physics is natural), the modern engineer often brute-forces solutions, and (lacking manpower) builds machines to apply that brute force. The ancient engineer employs manpower to assist nature in accomplishing the task for him. The further back in time you go, the more this must hold true, as there were fewer machines. The Romans themselves represent an intermediate step between mechanization and earlier techniques.

We use brute-force mechanization for its advantages, one of which is the reduction of manpower. However, it also eliminates the need for the intermediate steps that had previously been employed, and replaced, by mechanization. Eventually, the intermediate steps aren't even considered. After all, who would build giant ramps by hand only to tear them all down again? The answer: someone who wants to get the job done.

If we follow that principle backward, we can more readily see its application to megalithic works. Vitruvius himself (and it's in the referenced episode) describes enclosing a block in a wooden frame that effectively transforms it into a wheel and axle (Vetruvius, book 10, chap. 2, para. 12). allowing it to be easily rolled. Moving a huge block alone would be difficult, but the the Roman engineers did not do that; they moved a device of which the multi-ton block was a component. This is not secret, esoteric knowledge. Vetruvius' book was well-known. But it was forgotten and "re-discovered" several times.

(image source)
Such is the case with all such techniques, whether it's been re-discovered in the present or not.  For instance, obelisks were raised by using gravity, not working against it. A ramp would be constructed and the obelisk pulled up the ramp, base-first. Tipped over the edge, the obelisk descends upon its base by means of gravity. 'Magical' tech is simply not required. Then again, neither is advanced math or science. Just common sense: rolling is easier than carrying; dropping is easier than lifting. A wheel isn't just a mode of transportation; it's a wickedly accurate measuring device. Counterweights assist and levers multiply force.

Even when it pushes the dramatic tension (and let's not forget the sensationalist dross it must compete with), the Ancient Impossible series is a breath of fresh air.  It can help you to re-think the plausibility of ancient engineering feats so you don't resort to dismissing the accomplishments that deserve a healthy dose of respect.

And I highly recommend you read Vetruvius' work, as it will help you get into the mindset of an ancient engineer. Through it you can take a step toward understanding the past, and perhaps open up a mind that may have been clenched tight around baseless fantasies.

Since the online version has no illustrations, try this one [PDF].

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