This rather splendid piece of apparatus is sitting on a trolley just round the corner from my office. Mitch Guss uses it to demonstrate the use of the Ewald Sphere in indexing crystals for space group determination and data collection (for a tutorial on these concepts see Bernhard Rupp’s excellent Crystallography 101 course).
The printed web page (now there’s a slightly unphased concept) on top of the stack of overheads is from the Online Dictionary of Crystallography . In practise, we rotate the crystal using the goniometer (and see the annotation at Flickr ) and collect two diffraction patterns 90 degrees apart (about the axis of the incident beam) to index it. The whole thing rotates and twists quite pleasingly.
She’s beautiful, Richard.
So much kit, so little time to learn how to use it all.
But Richard, does it go ‘ping’? If not, here’s a machine that says I promise I’ll still love you in the morning
Henry, do you ever get the feeling you’re working on the Wrong Things?
Well, honey, if you need a big, expensive machine that goes ‘ping’ to simulate an activity that many people can indulge in for free, with no machinery at all, well… I’m confused now. What was the question?
“Does my goniometer look big in this?”, I believe.
I once had the pleasure of publishing this paper in which the researchers succeeded in measuring the oxygen consumption of individual bees in flight.
Measuring oxygen consumption in birds can be done by persuading them to wear little oxygen masks as they fly – even hummingbirds can do this. The problem with bees is that they breathe through tubes that come out all over their bodies.
The answer was to design an all-over oxygen mask – essentially a chamber in which the bee could fly and its oxygen consumption measured.
The problem was then of making an instrument sensitive enough to measure the tiny quantities of oxygen consumbed by a single bee. This demanded quite a lot of tweaks to the off-the-shelf equipment to lower the noise floor of the electronics way below its original design spec.
The final problem was that the machine had to be completely airtight. But a bee flying in a small airtight container might experience problems unless there was some flexible reservoir that could compensate for the shifting air movements. The answer was to glue a small plastic bag onto a tube coming out the side, which would inflate and deflate as required. The bag they found of the correct size and elastic properties was … hey, you’re way ahead of me here.
Altogether, a pretty amazing piece of kit, and a tribute to British ingenuity and resource, I’ve always thought.
Tell me Henry, Maxine, whoever: what’s the point of hiding 18 year-old papers behind a pay-wall? I can get to it via off-site Uni Library access, but sheesh. Bah. Humbug.
So. Yeah. I was right then. I wonder how they managed to type the sentence beginning “Just before entry into the sensor…” without falling off their perch? And how did you manage to edit it? I imagine the Nature office was a riot, that day.
I think we just allowed the authors
their headto say what they wanted. But yes, it was one of those memorable papers.Well, it certainly looks less
inadequacy-inducingscarydamaging than some equipment I saw in today’s Nature.Whoops, same link. Henry got there first.
Sorry about the subscription, Richard—can your library not set you up with remote access? See Juan Carlos Lopez’s latest, on value-added.
@Henry: the Irish are pretty good at ingenuity and resourcefulness too. A friend of mine once needed to collect saliva from a dog at 1 hour intervals over the course of 24 hours. (to assess gastric emptying rates after meals, in case you’re wondering). She eventually came up with felt covers to slip over the dog’s favourite ball, which she could then slip back off and centrifuge to collect the spit. She got me to help sew the slip covers the night before I went home for the weekend, leading to the strangest answer to the question “so what did you get up to last night?” that my Mum has ever received.
My friend, meanwhile, spent 24 hours throwing a ball to an increasingly exhausted and pissed off dog. And spinning spit samples at 3am. The things we do for science.
@Richard: A nice piece of kit that brought back some fond memories. I am just about old enough to have used a precession camera, though never for ‘real’ data collection: it was during a training course in Cold Spring Harbor in the very early nineties (which is still running). The precession movement is mesmerising to watch (how does the damn thing work?) and produced for us some very nice diffraction images of lysozyme (what else?). It’s a shame there isn’t a video to show the motion off to best effect… is there a movie feature on your digital camera…?
hah… I’ll have a think about that, Stephen. One for JoVE , perhaps?
Actually that would be really useful for explaining how this things work. Go on Richard, you know you want to!
mmm shiny… :)
I’m now giving you the same look people give me when I try and explain my patch-clamp rig…
Haha! But electrophysiology is just weird.
hah… I’ll have a think about that, Stephen. One for JoVE , perhaps?
Most probably yes Richard. I’ll alert JoVE’s Moshe.
Picture quiz – what’s this?
and has it got anything to do with this?
you and your bloody butts.
Well, at least they don’t go ‘ping’.
That can be … fixed.
Crikey. I shall have to circulate your photo to the Norfolk Border Police.
What, both of them?
Yes. They have two eyes.
Do they also have two aims and two ambitions?
It’s Norfolk, Maxine. Evolution stopped about 2.5 billion years ago, before bifurcation.
Sorry, Richard, I misread you. Yes, there are two border guards. One of them looks like this
and the other like this
(Sorry – that was a misprint – what I meant was
Being Norfolk, I know them personally, though not in the same way that my father knew Lloyd George (allegedly).
And it came to pass that Gee Senior knew Lloyd George
And Gee Junior knew a turkey known as Bernard
And Grant was thrown out of Nature Network for being egregious.
Which, interestingly enough, is derived from the latin egregius, literally ‘standing out from the flock’.
Here endeth the lesion.
:)
What was that you said once about knowing how to kill a comment thread stone dead?
Look mate, you’re the one who brought up condoms and, and and what I can only describe as H5N1.
I’m (and the estimable Drs Rohn, Neylon and Curry) quite happy to talk about serious scientific equipment.
What? Like this?
At least these are big enough to hide behind.
At least these are big enough to hide behind.
you have no idea how hard I am biting my tongue right now.
Just been reading this thread – absolutely hilarious. Thank you so much for brightening my day!