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Archive for January, 2012

Eilmer of Malmesbury, the flying monk, was a contemporary of William the Conqueror and made a moan about Halley’s comet which was seen in the spring of 1066. At that time, William was building ships for his adventure in England. Whether Eilmer was afraid William would come or afraid that he would not come but leave the English church in the hands of Harold Godwinson’s appointees, one might justly speculate, but in fact we know: War is never nice and never a favorite event of religious people. Brother Eilmer was already an old man, and he feared that William would destroy England. William of Malmesbury, a historian of the next generation, says Eilmer wrote of the comet:

You’ve come, have you? – You’ve come, you source of tears to many mothers. It is long since I saw you; but as I see you now you are much more terrible, for I see you brandishing the downfall of my country.

The comet was indeed bright, reputedly about four times the brightness of Venus. Everyone who looked up must have seen it.

But did he see it as a child? He says, “It is long since I saw you…”

Perhaps. But the periodic return of comets was not understood in those days, so possibly he saw another one. If he actually saw the 990 visit of Halley’s, which returns every 76 years, he must have been born in the 980’s. Long life, but those medievals who survived infancy and were not in the saddle (were not soldiers) generally lived as long as we do.

However that may be, even more than for his record of seeing the comet, Eilmer is known for his effort to fly. Somehow, after reading the story of Daedalus, he thought he would give it a try. He fastened wings to his hands, feet, and took a great jump off the top of one of the towers of Malmesbury Abbey. He says he glided 200 km, but the wind was unsteady and he had “forgotten” to provide himself with a tail to stabilize his flight. The crash landing broke both legs, and he was somewhat lame the rest of his life, though not bedridden. That distance of gliding means he was probably airborne for as much as 15 seconds, probably the most intense 15 seconds of his life.

He did not try again. He studied astrology, which in those days would have been a mix of astronomy and astrology. In other words, he knew the stars. The Church permitted astrology so long as it was not practiced in a manner that would deny free will or our first obligation to take our future from the hands of Jesus.

Brother Eilmer’s efforts at flight are interesting from the perspective that they show his curiosity and they also mean that the possibility of flight was actively on men’s minds, not as magic, but as something to be understood. They studied the wing shapes of birds – we know this from their drawings of angel wings – and they believed that air could provide a lift if properly understood.

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If we knew the names of the Mayan hydrologists, we would rank them among the great names in the history of technology.

The Mayans lived in a karst landscape on the Yucatan peninsula. A karst landscape is one whose bedrock is limestone rather than sandstone, shale, or some kind of igneous or metamorphic rock. The characteristic of limestone is that, while it may hold water in streams and pools, it is always eroded by the presence or passage of water. Shale repels water; we may find oil in shale, but not water. Igneous rocks – rocks from volcanoes – are too solidly constructed to allow the entrance of water into their structure. Metamorphic rocks – rocks that result from powerful compression – are also too dense to hold water.

Sandstone, however, holds water like a sponge, and the common wells, all over the world, reach into sandstone so that the water seeps from the sandstone into our pumping apparatus. No such well can be arranged in limestone. If there were to be a sandstone composed of shelly crumbs, and if water were introduced into such an environment, it would either erode the sand and carry it away in a white stream, or it would clog the crumbs with lime, and quickly close up their pores.

 

In that respect, limestone is like shale and the other unsandy rocks: water mostly sits on it or goes over or around it; it does not go through. However, a kind of well can be built through limestone, whereby an underground stream flowing through an eroded limestone cavern may be accessed and its water gathered for our use. alternatively, an underground lake can be accessed if you know where it is and can find a way to drill down to it.

Even so, a lake is not an infinite source of water. Every lake, above ground or below, depends on a constant water supply. Above or below, lakes are replenished by streams, which are themselves ultimately replenished by rain or snow. Stop the rain, stop the snow or stop its melting, and the lake has only a short life. The smallest lakes, ponds, fed by seasonal streams, are only seasonal for this very reason.

Now, the Yucatan has underground lakes which are called cenotes (three syllables: se-note-es) and they treated as reservoirs for use during the dry season. So much is simple enough. If you can find the lake and find a way to open a passage to it, and if you can keep the passage clean and protected, then you can use it. In the Yucatan, such discoveries were the original condition of settlement.

But it was the further genius of the Mayans – and originally, we may be sure, of a particular Mayan hydrologist – that they not only found these underground waters but they followed up by building more. In areas that lacked cenotes, they built enormous underground, stone-lined cisterns called chultuns and figured out how to replenish them with carefully collected surface waters. A chultun could hold enough water to carry an average of 25 people through the dry season. It was filled by directing water from surface spaces that look like plazas or roads of some kind, but these plazas dip just slightly, just enough to direct the seasonal rains into the chultuns. These collection spaces were kept meticulously clean; there is no trash in them, and no waste of any kind is allowed in the area. You know, when we have an archeological dig, we discover where cooking was done and where waste was collected and where things that fell were simply left where they fell. The collection spaces for the cenotes may have been used for play during the dry season, but they were not used for any purpose that left trash.

We do not know the name of the man who designed the first chultun, but this sort of thing does not spontaneously “evolve.” Somebody has to think through the entire design, the entire task of waterproofing, and the whole task of directing clean water into an access that is protected from animals, dirt, and enemies. After all that, everybody has to cooperate with the construction and maintenance of the whole system. For people who lived by the collection of seasonal rains, this was their life.

I am sure that the process was taken in steps – early chultuns were doubtless smaller, and perhaps there was a period in which existing cenotes were strengthened. In that sense, the chultun would have been the work of several inventive minds over a period of time. But I want to emphasize that an integrated vision of this sort is the work of a clear mind focused on a definite problem.

We do not know the name behind that mind – the Mayan writings do not tell us that much. We have names of kings and their children, but, at least so far, we do not have the names of the hydrologists. Still, they lived, and they had names, and at some period, long ago, those names were celebrated.

 

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Sharpless 2-106

One of the steady annoyances I get from the anti-scientific side of the classical renewal is silly remarks about how the romance of the night sky is destroyed by telescopes.

Good grief.

It’s true, there’s something special about looking at the night sky when you can lie back and watch the majesty of the Milky Way and actually sense the infinity of the sky. Not because it actually is infinite; it is not. But because there is no visible parallax, the impression of infinity is inescapable and it is part of the way that the heavens declare the glory of God; they draw us to reflect on the infinite call that does lie within us.

What a pity that relatively few people can see this kind of sky; fogs and smogs and just ordinary clouds often hide this majestic scene, as do buildings and even forests.

It’s a good reason to visit the dry and even the desert lands of this country – just to get a lovely dark sky.

Meantime, however, the telescope has its own stories to tell, its images that are not available without the enhanced vision of our best technology. One of the 2011 images from Hubble is this lovely nebula from some distant corner of our own Milky Way.

Sharpless 2-106

Visions of angels visions in the heavens

 

It’s a star-forming region, a place where new stars are forming as we speak. There are many such, the most famous being the one on the sword of Orion. But this one, called Sharpless 2-106 is about 2,000 light years away, which is to say that the image we now on camera is a record of a light display that was unfolding 2,000 years ago. In this image, the young stars and the light of their birth are recorded as golden light, and the central figure with its background of red rays and trailing ribbons is the consequence of neighborhood dust. There are other images online in which the figure is turned 90º and the golden portion is blue, the usual coloration for young stars. These are more dramatic, but not available for blogs.

It’s the end of the season, the visit of the Magi. I wish you a blessed New Year.

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