Some links: 80

Since 1835

Washington’s National Theater quite recently gave up its rope-and-sandbags rigging system: it was one of the last of the “hemp houses.” Rebecca Cooper has the story for Washington Business Journal, and there is good video about the transition to the cables-and-counterweights system (less flexible, but standardized) that most hands know.

Going back a little farther in time, a documentary short from the 1950s shows IATSE Local 22 loading in the National’s touring show of My Fair Lady.

Some links: 77

In transit

Joe Palca takes a ride on the personal rapid transit system on the University of West Virginia campus at Morgantown. The system was built in the 1960s-70s.

The concept feels strangely familiar. Somewhere in my boxes of files from B school I may have some lecture notes from Russell Ackoff. I seem to recollect that he had done some consulting on the psychology of transit riders that led him to promote the idea of small transit pods. In his view, what transit riders valued more than speed, or reliability, or short headways, was the ability to control who they shared a vehicle with. Hence, big city busses, not so popular; private automobiles, very desirable.

On the boards

A very nice piece by April Peavey about the electro-mechanical flip-flapping annunciator boards that have all but disappeared from American train stations. I now know that they can be called Solari boards, after the Italian manufacturer that first introduced them in 1956. Maybe I realized, but have forgotten, that the letters and numbers flap in only one direction, so that the transition from an E to an H, for instance, takes much less time than for an S to an A—and hence the new destination or train name is displayed one letter at a time, as the individual units cycle around. It’s that gradual reveal that I remember, like watching a photograph develop, or like playing the word puzzle from Wheel of Fortune in real time.

Alas, the news peg for this story is that Amtrak is replacing the Solari board in Philadelphia’s 30th Street Station, where many years ago I would wait for the regional train to New York to take me back to my internship.

Under pressure

Callan Bentley turns the screws on a diamond anvil cell. Pressures inside the cell, a little gizmo smaller than a snow dome, are on the order of 60 GPa. He writes:

  • 60 gigapascals is therefore a pressure equivalent to about 2100 kilometers of depth in the planet – most of the way through the mantle, though not quite to the outer core (which is at ~2900 km depth).
  • A pressure cooker cooks at 0.0001 GPa.
  • Your car’s tires are inflated to a pressure of 0.0002 GPa (2 bars, or ~30 psi).
  • 60 GPa is a lot more than 0.0002 Gpa.

(Sorry, but I had to go to that song.)

I’m with you on the illegible part

In a quite useful five-part series, Steve N.G. Howell explains how field notes work and how and what you might want to record, either in the field or in the motel at the end of the day. He saves the best advice for the last installment:

In conclusion, your notes are your notes. Write what you want, but in later years you’ll only have yourself to blame if your old notes don’t contain the information you find you want. If you have time, write it all down. If you don’t, pick and choose. But whatever you do, or don’t do, the main thing is to enjoy birding.