Tag: vintage

More Sodium

Posted on by Brian Garthwaite
You’d think it would be more complicated inside.

Here, our more modern sodium light sources, using a clever design that enabled a reduction from the minimum 35W to as little as 18W in 1977. Cool, yeah?

Unfortunately, Philips finally bowed out of the low pressure sodium lamp game in 2019, mean we’ve got these dinosaurs running for as long as we can scour spare lamps online. Once the supply’s gone, it’s gone.

Pure sodium!

Hey, look! Sodium metal! Highly reactive, so it’s inside with a mixture of 99% neon and 1% argon, neither of which deigns to react with, well, anything. That’s why, when it starts up, we see a purplish glow from the noble gases before tube reaches 260°C and vaporizes the sodium. After that, it’s an intense monochromatic yellow-orange that’s hard to look at.

Low Pressure Sodium

Posted on by Brian Garthwaite
Burnt-out low pressure sodium lamp
Toast.

Remember the old, aggressively-yellow street lighting that pre-dated LEDs, ceramic metal halide, and high pressure sodium? Turns out it’s very useful for physics, as the two strong emission lines near 589nm are handy for various experiments.

The lamps themselves are fairly tough, and the ballasts that operate them even more so. But, eventually, they burn out.

General Electric ceased production on these lamps back in 1972. So, no, sorry, replacements are not readily available.

Part 1

Posted on by Brian Garthwaite
Ditto of Math 101 final exam, part 1, from November 15, 1948
Ditto!

Astronomy, here and elsewhere often under the Physics umbrella, was once part of the Mathematics department at Bucknell. Occasionally, we’ll stumble across some old files in the Observatory that have been yellowing gracefully for decades. Like this two-part final exam from Math 101. Algebra!

Of note for context: this old exam – November 15th, 1948 – waited patiently in a filing cabinet at the current Observatory, built in 1963. In all likelihood, it sat in a folder in the old Observatory for thirteen years, transferred to Tustin Gym for a time, and then quietly continued to be forgotten in a new building until some tech decided to clean the place up a bit.

Who doesn’t love finding curiosities in purple ditto ink?

Perforations

Posted on by Brian Garthwaite
Perforation in library book page reads "Bucknell University Library"
Better or worse than a rubber stamp?

Old texts from the library sometimes still have these perforated markings, ensuring that no one forgets that this particular copy of Morse’s Vibration and Sound, from the International Series in Pure and Applied Physics, isn’t the same one that Grandma’s reading for her book club. They’re kind of charming in their own way, a means of labeling texts that disappeared at some point.

Presumably the librarians could enlighten us on that point, were we to ask nicely.

In the meantime, we’ll just muse over the idea that for a time, some individual had to take every new acquisition and punch a few of these before the first shelving. Some dedicated machine sat on a desk just for this purpose. And when it was a big day, those little punched-out chads probably got everywhere. The spilled glitter of their day.

Leonids

Posted on by Brian Garthwaite
Meteor counting log, Leonids shower, from November 1934
Up to three per minute!

Ninety years ago, during the Leonids meteor shower, someone was counting a lot of burning bits of debris from comet 55P/Tempel-Tuttle. With one fifteen-minute window boasting forty-five meteors (!), that’s a powerfully active shower. Not quite a storm, but those happen with the Leonids sometimes.

According to NASA, the Leonids peak about every 33 years, with 1966 being a spectacular meteor storm. In one fifteen-minute window, thousands of meteors fell like glowing rain. How amazing is that?

Also: check out the times indicated. We’re assuming the counting started at 11:00pm and ran until early morning, with a 24-hour clock opposite how we’d expect it. (Maybe sleep deprivation?) Either that or it was a truly spectacular meteor shower!

Metersticks

Posted on by Brian Garthwaite
Three metersticks
Various vintages.

In our Physics & Astronomy labs, we use metersticks with great frequency. Often for measurements, sometimes to approximate distances that make the arithmetic easier, and occasionally as a handy tool for pointing to the projector screen.

They aren’t super-high precision any more than the rulers you remember from elementary school, and for that we have other tools. Sometimes, as you can see above, the years have warped and twisted things a bit. We adjust.

As you might expect, they offer metric distances on one side, inches and feet on the other. The best ones – the oldest set – were long ago painted black to conceal those SAE units. Clearly, someone grew weary of students measuring everything in inches and then complaining that the math wasn’t working out right.

Force Table (again)

Posted on by Brian Garthwaite
Force table surface, etched with date of purchase and price paid. From April 1964 for $96.75.
Cast iron holds up.

We’ve pointed out our old and reliable force tables before – classics of the undergraduate physics experience – which arrived here in several installments. Previously, 1957. This young’un only appeared in April of 1964, intended for the Physics 107-8 lab. Not listed in any recent course catalog, we’re uncertain of exactly what that was.

We could probably go pester some librarians, because surely there’s a record, but those folks are awfully busy on more important matters. Leave the idle wondering to the fellows here in the basement.

At any rate, they paid a healthy sum of $96.75 for this precision-machined beast. In today’s dollars: $985.65.

Do you think we’ve gotten our money’s worth yet?

Slide Rule

Posted on by Brian Garthwaite
Large demonstration slide rule
Larger than is typical.

At one point in time, the slide rule was an essential tool in a physics/math/engineering education. Built and etched with high precision, they enable a skilled user to perform all sorts of mathematical operations with speed and ease. It’s the power of logarithms in a hand-held device.

Which, if you’re the sort of person who can master a slide rule, means you can also fully grasp the particulars of how one works.

It’s a smidge harder to get there with an everyday calculator. The gulf between the solid-state electronics inside one and the button-pressing interface is enormous.

Large demonstration slide rule
Concrete blocks: 16″ long.

At one point in time, this beast was a handy demonstration device at the front of the lecture hall. Visible from way in the back, it lets an instructor illustrate proper slide rule use to an entire class at once.

Not that that happens much anymore, but this thing is awesome. If you found one back in the closet, you’d keep it handy, too.