Up there, in the mist and passing clouds, is a yellow crane: not the bird, but the manmade mechanism whose arm rises as it lifts heavy objects, moves sideways somewhere, then lowers as it deposits them. How can a heavy machine like a crane stay so high and move around with such seeming ease? Mist and passing clouds always conjure up mystery, although the mystery is in the thing they seem to obscure.
“It’s like a praying mantis,” Alison says, looking through the window at my side.
In my own mind, I resist the figure of speech. Analogy says something is like something else, denying it its own reality. Besides, even if the yellow crane has the aspect of a praying mantis and its extended head, the insect is about destroying what it grasps in its deceitful arms. A crane is about building. Also, unlike the insect, a crane has no self-awareness. It’s a piece of equipment.
I ask myself how cranes came into being. The basic outlines will be both intuitive and logical. Just as nature evolves and natural selection keeps around only what thrives, so do manmade things. First there has to be a need, and from that need an idea, and from that idea a practical application. Back in the days when hunter gatherers settled down as farmers, no one thought, ah, let’s build skyscrapers and attach cranes to their sides to enable the transfer of heavy and unwieldy materials. Instead, desiring shelter, they imagined and then built huts, made of such local materials as stone and adobe clay. But in time humans dreamed of bigger and better buildings. To build big, they needed to lift, carry and drop heavy things. Undoubtedly that’s how the idea of a crane came into being. A little Googling tells me that it looks like the Egyptians used a kind of crane to help workers move heavy blocks around and up the pyramids as they were being constructed. Cranes, then, have been around not just for centuries, but millennia.
Even so, cranes remained fairly rudimentary for a very long time. I’m guessing the next evolutionary step required factories, which are both containers of machines and themselves machines. Out of factories came the machines that made other buildings, just as today’s robot manufacturers, such as Japan’s FANUC Corporation, use robots to build robots.
The skyscraper came to New York over a century ago. I assume high-altitude cranes were invented to meet their construction requirements.
That’s as far as speculation takes me. I see I’m seeking to dispel mystery, any notion that the distant yellow machine could be some kind of miracle. Rather than stand next to Alison in awe, I stare in order to explain. It’s a habit of mind in our scientific age.
Yet the more I think about these machines, the more curious I get. So I delve a little more deeply.
The mechanical device called a crane is named for its resemblance to the long-necked bird of that name. Makes sense. But I’m surprised to learn that the distant origin of the bird’s name is a verb meaning “cry hoarsely.” Curious that the name originates in the sound the crane makes rather than its distinctive appearance.
Why yellow? The mechanical crane’s bright yellow color alerts people of possible danger: If precautions are possible, take them. I don’t think of the bird crane as yellow, although websites mention yellow crowns and yellow plumes. To the extent both have yellow color, it’s apparently coincidental.
Then I learn that the yellow crane in the clouds beyond our window is called a tower crane. It perches on what they call a “mast.” From this distance, the mast looks like an upright erector-set girder. As I understand it, each time a new floor is ready to work on, the mast structure is built up to that level and the crane raised with it. To keep the crane from falling over, its specially-dug base is “bolted into the ground and weighted down by giant blocks of concrete,” while the winch’s load is balanced against concrete ballast blocks. After a certain height, stability requires that the crane be attached in some way to the building.
Contrary to my assumption, the tower crane we know today wasn’t invented until the late 1940s by a German company to help hasten post-World War II reconstruction and only afterwards brought to New York. I’m not clear how far developed tower cranes had been to that point, but the German contribution was to enable a tower crane’s cab and winch to rotate. Now, not only can a tower crane pick up objects from the ground and deposit them at a higher level; it can also pick up objects from one area of the floor and turn to deposit them on other spots on that floor.
Then I wonder how the crane operator reaches the cab. Some buildings under construction incorporate an elevator in a shaft that rises as each floor is added. Sometimes a construction company will build a temporary exterior elevator. But if there’s no elevator, the operator must climb all the way.
To my mind, operating a high-altitude crane is inherently dangerous. It seems to me the snapping of a single rivet in the erector-set mast could bring down the entire crane support or a sudden big gust might shake the cab off its mooring. If I were in that cab, I’d be terrified. My most frequent nightmare, which sometimes jerks me awake, is of standing on a high precipice of one kind or another.
In fact, I learn that the cab sways in the wind. It is designed to, by as much as three feet in each direction. A St. Louis crane operator says that he tries to get out of the cab on seeing signs of a coming storm. If he fails to, he must stay there, buffeted by the winds.
Here in New York City, several tower cranes have crashed, causing death, injury and property destruction. Now, here and probably also in St. Louis, tower cranes must shut down if relatively strong winds (twenty miles an hour or higher) are forecast.
Alison says crane operators aren’t just a union, but a close-knit circle who wear jackets announcing their trade and their affiliation. These are proud men who brave the weather and physics to get their machines to perform monumental tasks at high altitudes.
Late in my research, I encounter the concept of “crawler cranes,” which may encompass mobile tower cranes. I’m not sure, but I’ve done as much research on cranes as I care to. I now have some idea of the tower crane’s history and how they work, and I’ve learned a few terms of art.
Despite my research, the yellow crane remains something of a mystery. To explain isn’t always to demystify. When mysteries are about good things, they feel rather like miracles. For me, the yellow crane is a kind of miracle, in part because of its remarkable function, in part because of its altitude, in part because I’ve been contemplating it in mist and clouds.
“Miracle” is roughly defined as an event that defies the laws of nature. But the awe I feel for the yellow crane makes me think the definition is too restrictive. In that light, we take most miracles for granted. Skyscrapers are miracles made ordinary by the thousands of people walking by them every day, and the tower crane has become just one more part of the urban landscape. If pedestrians give any thought to a yellow crane way up there, it’s from fear of its crashing down.
The Internet is a newer miracle, already taken for granted because we use it for shopping and sending birthday greetings. Yet the Internet has no tangible infrastructure. True, access requires smartphones and personal computers, cables, plugs, charging stations, and other hardware, but all this paraphernalia is ancillary to the vast unknowable we’ve come to call cyberspace. And that’s another way we neutralize miracles: by naming them.
Days later, the yellow crane out back is still at the top of that building, and it is still mysterious. Visible off-and-on between scudding clouds, it moves. Its arm, which I now know to call a winch, has lowered. Now it rises, then rotates around, the yellow cab turning with it. Then a cloud obscures it completely.
The next moment, the yellow cab reappears. It makes me think of the sun, an even bigger miracle, rising (from our earthly point of view) on a fixed schedule and keeping the world able to support life, and through the lives it sustains, the lesser miracles those lives perform.
The yellow crane is an analogy after all: It made me think of the sun. And it’s symbolic in other ways: humankind rising above nature, aspiring to the heavens. I shouldn’t have been so resistant to Alison’s comparison to a praying mantis. I now picture it that way myself.
In a few days or weeks (I have no way of estimating), that fourteenth floor will be finished. The crane will be ratcheted up another ten or more feet on its mast, and construction on the fifteenth will commence.
And someday after that, the building’s basic structure will be complete. We’ll probably miss the crane being taken down, and anyway, from this distance it would be hard to follow. Then the yellow crane will have moved on—flown away—to perform another miracle on some more distant construction site. It’s a bird after all, just like its namesake.