Name this piece of historic lab equipment


Do you know what this is?

Science blogger Southern Fried Scientist found it in a cabinet in his laboratory. It's got a motor, which turns some kind of centrifuge, and a set of optical lenses, which appear to be focused on the center of the centrifuge drum. It's made out of Bakelite and steel, and the older scientists in his lab agree that it's probably early 20th century vintage. Whatever it is.

One final clue, two patent numbers that are written on a plaque which also identifies Bausch & Lomb as the makers of the optics—# 1,648,369 and # 1,907,803.

What do you think, Boingers?


  1. Well, the first patent is from 1927 for an analytical centrifuge and the second is from 1933 for a microscope-centrifuge.

  2. Moving boundary sedimentation setup, would be my guess. you load you sample atop a cushion of increasingly more dense solution, add a dye (usually fluorescent), and track its progress down the gradient versus time to get information about the nature of your analyte.

    1. I don’t know if I have a “don’t know what it is” but: do you want it?
      Ha ha !

  3. It looks somewhat like an old piece of equipment for looking at spectra lines that was floating around my old high school.

    But I think the patent numbers are more reliable than my memories of broken physics demo equipment, and visually it looks like I’d expect a centrifuge scope to look, so that seems very plausible.

  4. The object top left with a wire coming from it is a lamp for illumination. The eyepiece is stationary, top right, but the objective is going to be spinning with the centrifuge. There will be a mirror in the center that spins with the objective to send the image up into the eyepiece. The cylindrical object sticking out the bottom marked “Dumore” is the motor powering the centrifuge.

  5. I was thinking something on the order of an analytical ultracentrifuge but not as fast obviously. A lot of stuff of that style and vintage was for separation of blood but I don’t know why you would have to visualize it. I also would not turn it on, old centrifuges are almost as bad as finding unaccounted for radiation somewhere(we had this old guy retire and he had more rads in the cold room than you are even allowed to buy today, ugh).

  6. Its pretty obvious from the way the light is used to illuminate the chamber that you are not viewing the center of the centrifuge chamber but the sides; there is most likely a mirror at the center which reflects an image near the lit area.

    Still the question remains as to what this is for.

  7. It’s got a modern brass light socket and the eyepiece looks modern as well. I wonder if it’s got some kind of biologic or medical usages, such as examining fluid patterns while spinning at various speeds.

  8. A bit of research turns this up: the 1933 patent belongs to biologist E Newton Harvey (source:, who worked with Alfred L. Loomis ( Loomis created the first prototype in 1930 for his private lab in Tuxedo Park, NY.

    Apparently, Bausch and Lomb was already sniffing around the concept in 1931. After refining the concept, Harvey patented his version in 1933.

    Someone has to have a scan of an old B&L catalog…

    1. Wastrel wins it, because her link shows that the mercury vapor lamp is discharging synchronously with the drum speed, so that the same spot on the drum is illuminated once per revolution and the image is reflected straight up the central axis of the drum and into the eyepiece.

      It’s a tool for observing things being tortured in a centrifuge.

  9. Might the “light” actually be a strobe, synch’ed with the rate of rotation, to allow a non-blurry view of a specific point of rotation?

  10. @wastrel

    … and just from a visual examination, it appears the patent is validating my guesstimate about the mirror in their being a mirror in the center reflecting an image from the lit area.

  11. Wiki: “Theodor Svedberg invented the analytical ultracentrifuge in 1925,…” Svedberg is listed as co-inventor on the earlier patent.

    Wiki: “In an analytical ultracentrifuge, a sample being spun can be monitored in real time through an optical detection system, using ultraviolet light absorption and/or interference optical refractive index sensitive system. This allows the operator to observe the evolution of the sample concentration versus the axis of rotation profile as a result of the applied centrifugal field. With modern instrumentation, these observations are electronically digitized and stored for further mathematical analysis. Two kinds of experiments are commonly performed on these instruments: sedimentation velocity experiments and sedimentation equilibrium experiments.”

    Basically, it’s a way of watching how molecules stay together or not and measure interesting things about them.

    1. Nice find, and probably why none of us could figure it out, so far as I can tell those experiments are totally pointless, although it does remind me of a device that was purported to separate X and Y chromosome carrying sperm (X is heavier, but you may need an ultra for this too) so that you could decide whether you wanted a boy or a girl. Still I think that sometimes machines are invented because they can be and not for a specific scientific purpose. A lot of scientists in those days were people who had money and wanted something interesting to display, but the fact that this was found in a lab suggests it might actually be useful.

  12. dculberson looks to be right.

    “THE microscope-centrifuge, recently described by Harvey and Loomis (1930), was
    devised in collaboration with Mr Alfred L. Loomis and constructed in his private
    laboratory at Tuxedo Park, N.Y. It is a device by which living cells can be observed
    while they are being centrifuged at speeds of 1000 to 4000 R.P.M. at a distance of
    11 cm. from the centrifuge axis. The instrument is really a special head, containing
    part of a microscope, built to fit a \ in. shaft, the size of the type SB International
    Equipment Company electric centrifuge. The scheme is as follows.
    A microscope-objective (Obj) is firmly set into one end of a bar of metal which revolves
    on the centrifuge axis (Fig. 1). The objective is purposely reversed from the ordinary
    position on a microscope so that the light (L), the focusing screw (F), and the slide containing
    living cells (S), will be easily accessible on the top of the centrifuge. After passing
    the objective, the light is carried by two total reflecting prisms, A and B, to the axis of the
    centrifuge and then vertically upward. The eyepiece (Oc) is stationary and mounted
    permanently in the protecting cover above the axis of the centrifuge. The counter weight
    (W) is used for balancing.” (E.Newton Harvey, Princeton University, December 18th 1930)

  13. Just as I thought, all blurry. What is the point? Do we also need a car-mouted telescope for rapid road inspections?

  14. Heh: looks like we all hit the same two or three pages on Google simultaneously. But this was obviously manufactured by B&L – we need to find an old catalog that contains this sucker.

  15. for those with a good library

    “The centrifuge has been used in experimental study of living cells for several types of investigation. First, to determine relative specific gravity and total volume of granules (which are stratified under centrifugal force) present in living cells. Second, to observe the behavior of mitotic figures and other surface of slide in which cells are thrown by the structures under centrifugal force, experiments which centrifugal force. Third, to measure the viscosity of the protoplasm, by applying Stoke’s law to the rate of movement of granules under the centrifugal force. The previous procedure has been to centrifuge the cell in capillary tubes, remove it from the tube and observe it under a microscope to determine what happens.”

  16. Now that the function of the beast is settled, take some more (hires) pictures and put them on Wikipedia Commons, please!

  17. Now I have images of uncaptioned quasi-Far Side cartoons bouncing around in my head, featuring amoeba-type things with 1960’s Mercury-astronaut-in-centrifuge facial expressions.

  18. You know that spinny thing NASA put astronauts in during training? Well this is the same thing for sea monkey astronauts. And, obviously, the microscope is for the scientists to see when and what the sea monkeys vomit.

    1. Q: What’s a henway?
      A: About 3 pounds

      haha, hen weigh …get it?

      some good old tomofoolery…thanks anon

  19. By the way, the Dumore (NOT Dunmore) photo from the original SFS post is a red herring; that’s just the serial for the motor, which was produced for Bausch and Lomb.

  20. And for the record, the next and only thing anyone should be doing is contacting the Archives Dept. at Bausch and Lomb.

  21. This is an analytical centrifuge. That type of centrifuge was used extensively in 1950-1980 in biological labs and is still in use. It allows for the measurement of sedimentation constants (which has unit of svedberg, one of the authors on listed patents), sedimentation rates etc. I believe that type of DNA replication was proven using one of these machines, which then allowed elucidation of DNA structure by Watson and Crick.

  22. As far as I can tell, in this design the mirror will not rotate with the centrifuge, but instead is fixed to be permanently looking back towards the crook of microscope.

    The light above the centrifuge is fixed. In the roof of the centrifuge there is a single hole. This implies that as the centrifuge turns, the hole will pass beneath the light, briefly illuminating the slide. So this will essentially work as a strobe light, illuminating the slide only when the slide is facing away from the viewer (towards the crook of the scope).

    So this implies to me that the viewer is only looking at the slide on that one point, and the strobe effect will make the slide appear stationary. Because the strobe effect is caused by the turning of the drum, the image will always appear stationary regardless of the speed that it is turning.

    My guess is that it is working this way instead of using a turning mirror because even a slight shift in alignment as the mirror turned would cause a blue in the image. This way the mirror can be fixed, the point it is looking at is always the same, and the image will always be sharp.

    1. … that should say “even a slight shift in alignment as the mirror turned would cause a blur in the image…”

  23. I love how someone kluged a $1.99 hardware store lamp socket onto what must have been an incredibly expensive (at the time) piece of gear. Talk about never say die!

  24. In fact, websorcerer’s link above confirms my hypothesis that the light was designed to strobe onto the slide, but adds an important addition:

    With each revolution of the centrifuge the contact point (C) on the bakelite disk (E) discharges the 2000 to 3000 volts through the mercury lamp, and during the remainder of the revolution the condenser is again charged through the high resistance and is ready for another discharge

    So the strobe effect wasn’t just caused by the hole passing under the light, but the rotation was actually triggering the strobe to fire. This would probably give you a much more precise strobe light when the slide was exactly in the same position, instead of just using the rotation of the hole.

    I’m pretty sure that this confirms that the mirror is in fact fixed (w/r/t the eyepiece), and that you are constantly seeing the slide at the same point in the rotation.

    1. I think you’re right that the mirror is fixed, and I think you were right in your first comment that the strobe effect is achieved through the hole in the centrifuge cover. That lamp socket is not the right type for a mercury vapor lamp, and the wiring doesn’t look right for a strobe lamp synced to rotation anyway. I’m willing to bet that there’s a standard 2-pin 120v plug on the end of that brown zip cord.

      I suppose a misalignment might cause a “blue” (rather than a blur) if the centrifuge was spinning fast enough! You know, close to c, the speed of light. It would cause some time dilation and the mirror wobbling closer the the eyepiece would cause blue shift and away from the eye piece would cause red shift. Then the space baby would pop out of nowhere and detonate an orbiting atomic bomb.

  25. The posters above are probably right, but I think you may want to try a couple things before jumping to any conclusions.

    1. Rub the side and make a wish.

    2. Put it in a DeLorean, et it spinning, and speed up to 88.

    3. Put a gold coin in it and start it up. It may produce 2 gold coins.

    4. Attempt communication via Morse Code with strobe light.

  26. Thanks everyone for your ideas. I’ve contacted the Bausch and Lomb Archives and they have someone looking into it. Both analytical centrifuge and microscope centrifuge seem to describe it, but there has been some kludging on the inside, so someone may have had their own plans for this particular scope.

    Some more details:

    The light source is a 660-watt bulb, but not mercury vapor. The mirror is fixed and points back towards the cradle. There are two slots for samples (or perhaps a sample and a standard), both of which pass under the light. The light fixture is completely independent of the centrifuge, so I don’t believe that it strobes in time with the rotation. The scope number is 242,181 and Bausch and Lomb celebrated the sale of their 250,000th scope in 1936 (source: so it probably predates 1936.

    One sample container has been modified to accept two capillary tubes, while the other takes some kind of slide I’m not familiar with. Two razor blades have been glued to the inside of the light fixture to create a very narrow slit, leading me the believe that whoever used it was doing something with polarized light (which also fits with the history of the room it came out of).

    1. From your description of the mods, I would go with a very Rube Goldberg version of an analytical centrifuge.

    2. I’m a little confused as to why you needed the BoingBoing commenter’s ideas. Looking up the patent numbers not only tells you what it is, but also how it’s put together and how it’s used.
      Sure, it’s funny to see how many people call it an electric bong or a spirograph, but there’s easier ways to find out exactly what this is…

  27. I would think the slide would hold a reference standard and the capillary tubes would hold the analyte and you’d run it until the two matched up zoetropically (yes, a made up word), maybe as a part of a separation/purification process?

  28. Believe it or not…
    This is the first true cell phone with picture phone capability.
    The slot on the left side of the coin holder is where you insert coins to pay for a call.
    The dome toward the top left was an early call waiting, recording indicator.
    The plug is for charging the battery.
    It is characterized as “lab equipment” because in order for it to work you had to carry the lab with you.
    Telephone labs are not new!

  29. It’s for making contact lenses; that’s my first thought. After reading all the comments I still think it is for making contact lenses.

  30. its a turbidimeter.

    a liquids turbidity is the ratio of the amount of light that passes through the liquid to the amount that is scatter.

    A very useful tool for either the brewing industry or the chemical manufacturing industry.

    hopefully a more condensed version of the otherwise technical, correct, identifications.

  31. GadgetGav got it. Those are US patent numbers listed on the machine. One common use for it would be to measure hematocrit.

  32. I think it could be useful to separate blood plasma, and measure Hematocrit as someone said.

  33. Well, it’s simply an early phenakistoscope. A disc with different frames rotates thus making an animation. Then the scientist peeps inside to look at vintage pornography between stressful experiments.

  34. I think it’s an early version of the disc centrifuge, commonly used in these modern times to measure particle size distributions of colloids and suchnot.

    You put a dilute dispersion of whatever you’re interested in in the middle, then you spin it around really fast until the particles move through your field of view (which is somewhere out toward the edge). Bigger particles will move faster through the fluid, so you’ll get separation based on particle size. You’ll end up with a graph that’s number of particles versus time. You can use densities, g-forces, distance, and Stokes’ law to translate that into number or mass fraction of particles versus particle size.

    Nowadays they have a detector of some sort (lasers?!), so you don’t have to actually watch through a microscope to see the particles flow by. But all the other elements appear present.

    That’s my guess!

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