Tag: storage

Acquisition Dates

Posted on by Brian Garthwaite
Optics rail acquisition 9/27/43, for $40.00
Most impressive is that the yellow paint has lasted this long.

It seems the university has drifted away from this, but if you look around at old equipment, a great deal of it is marked with the date it was acquired and – if it’s old enough – the cost. They’re fascinating glimpses into the past.

Here, an optics bench made by the Central Scientific Co. of Chicago, Illinois. Or, as they’d prefer, Cenco of Chicago, U.S.A. This particular 132cm chunk of cast iron and steel joined the department in late September of 1943, for the low, low price of $40. According to the U.S. Bureau of Labor Statistics’ CPI Inflation Calculator, that’s an excessively specific $681.17 in today’s dollars. (Significant digits!)

Cenco plate
Surely there’s a reason for the cities listed in that order.

Up until now, it’s been in more or less continuous lab use, only recently replaced by brand-new extruded aluminum optics benches. Almost 80 years, and they’re not entirely kaput just yet.

After all, if an apparatus continues to be useful, we’ll keep it around. This one is getting repurposed for future labs, so we’ll see how many more decades it has in it…

Radio knobs

Posted on by Brian Garthwaite
Drawer full of knobs
Drawer label says “Radio Knobs,” and that’s actually what’s inside.

There’s a tendency in the shop to scrounge and save almost everything. You never know when something might come in handy, and experience has shown, over and over, that there’s value in all but the junkiest junk. And even that, if sufficiently large/heavy/whatever, can be an effective doorstop, or spray paint shield, or otherwise helpful bit of plain old physical mass. When a piece of equipment breaks and is just irreparable, you dig out the good bits and set ’em aside.

It’s important to keep track of which boxes contain the useful bits and which the junk. Sometimes the difference isn’t immediately obvious.

There’s a drawer in one of our storage rooms labeled “Radio Knobs.” Indeed, that’s what’s inside. Collected by our predecessors from an array of broken equipment, calmly waiting their turn to be useful once more.

And, yes, they have been useful.

Fulgurites

Posted on by Brian Garthwaite
Box of petrified Jersey lightning
“Petrified Jersey Lightning”

We have multiple storage rooms, each with shelves, cabinets, drawers, and seemingly endless places to tuck away small objects. It’s easy, so easy, to simply forget something. Then, years later, someone else gets the joy of stumbling across it.

Sometimes it’s a century or more.

Petrified Jersey Lightning

or

Fulgurites from South Jersey collected by John G. [unknown]

Presented to Physics Dept 1/14/10

Fulgurites!
Neat!

That would be January 14th, 1910.

Fulgurites are a mineraloid formed when lightning strikes the earth and fuses mineral grains. They come in as many varieties as there are different types of soil, and as we’re in Physics, not Geology, our understanding of the particulars is as reliant on Wikipedia as yours.

We can only guess as to why John gifted Physics with these 112 years ago, but we appreciate it. Everyone should have the chance to stumble across a little petrified Jersey lightning from time to time.

Drinking Bird

Posted on by Brian Garthwaite
Drawer full of drinking birds
Happy bird!

Greetings from one of the unofficial mascots of Physics, the drinking bird! Forever wearing its top hat, this classic toy is found all around the department. Though we keep a drawer full of them in storage, there are a handful about the shop shelves, professors’ offices, and occasionally elsewhere. The drinking bird is an example of a heat engine, which converts heat into mechanical energy.

Drinking birds are especially fun because they operate at room temperature. Two glass bulbs are connected by a tube and filled with methylene chloride, which has a low boiling point and condenses and vaporizes readily within the vessel. When the upright bird’s felt-covered head is wet, evaporative cooling causes a vapor pressure differential between the two ends. As liquid from the bottom rises, the bird becomes top-heavy and leans down for a drink, re-wetting the felt and priming the process to repeat. It’s an entertaining demonstration of the effects of various laws of physics.

There’s the ideal gas law, of course. Temperature change causes pressure change, which causes a shift in the balance of liquid and vapor. That shift in mass results in a center of mass that oscillates from one side to the other of the fulcrum, creating torque and movement. For as long as the bird can re-wet itself and maintain the temperature differential, the heat engine will continue to operate.

Alternately, you can apply a heat source to the lower bulb to get the same effect, which is the basis for most heat engines. There are many options to produce heat, and a wealth of engine designs to turn that thermal energy into useful work. But few are as simple, visually apparent, and entertaining as a bobbing glass toy.