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[ta0]

EDIT: I split and merged the main posts about the "Maxwell" top into one thread.

Ok, I got to the start of the Japanese section. So I have these remarks and questions about the scientific toys section.

You mention both James Clerk Maxwell and Crabtree's book. On pages 8 and 51 of Crabtree there are drawings of the remarkable "Gyroscopic Top". I read this was invented by "a professor Maxwell" but it did not specifically say it was THAT Maxwell. Do you know if that was the case?
.  .  .

Thank you for your informative answers, Lourens.  I love the fact that you play with the tops in your collection!

I have a nice reproduction of the "Maxwell top" identical to the one on Crabtree. This is the brochure that came with it:

A top very similar to this one was designed by a British professor over 100 years ago as a device to demonstrate gyroscopic principles to physics students. Specifically, Professor Maxwell wanted to be able to show, as convincingly as possible, that a gyroscope will always react at 90° to an applied force.

If you do an internet search for "Maxwell top," you find several from lab classes at universities, but generally without the upper track, so the name Maxwell is probably correct. Note to johnm: you should make one! (the attached paper from Caltech even has one floating on air).



However, I am now convinced that it was made by a different professor Maxwell. First, if the top had been know in 1890, Perry would have described it without doubt in his book, so it must have been created between 1890 and 1914.  Second, Crabtree wouldn't have failed mentioning that it had been invented by the famous physicist.

[Lourens]

Hello Ta0,

I have the same top from the 1970's and it is called 'Ptolemeus' (Ptolemy) after the Greek astronomer.I think that the maker of this top looked for interesting names for his product. Maxwell and Ptolemy were names that could help selling products! On page 8 of Crabtree (footnote) says that this top could be purchased in that time by Newton and Co. Also interesting name and a link to science in general.

Lourens

[johnm]

Note to johnm: you should make one! (this paper from Caltech even has one floating on air).

We already have the same version in our lecture demonstration inventory.  It gets some action every year at the science fair, but I suspect it has never been used as part of a class discussion here.

Thanks for the link to the physics lab exercise!  I'll file a copy with the partial plans we have to make a mechanical assembly to help discuss Euler coordinates which have been sitting unattempted for at least 10 years.

[ta0]

.   .   .
While looking around that online database I found a catalog (Ducretet, 1905) with the Maxwell / Ptolemy top we had discussed before.  It is credited a certain M. G. Sire (as several other gyroscope-type instruments in the catalog) who wrote a 1862 monograph about instruments for the study of rotations. So now we may know the real inventor.

I did a search for the monograph by Sire and I found the whole thing thanks to Google inside books (amazing)! It starts here but the section corresponding to the "Maxwell" top is here and this is the corresponding plate.



The section title is "Perimeter Rotations" and it says that it can be seen with the help of devices such as M. Henri Robert's device or a spinning top. Robert's top is described in the previous section ("very ingenious" he writes) and its main purpose is to be able to adjust the support point of the top so it can be in a range of positions below, at or above the center of gravity. It only needs the hanging spiral to become a "Maxwell" top.  At the end of that section, Sire describes arbitrary tracks, and even the possibility of having a set of tracks in something like a daisy wheel for easy swap. Unfortunately, he does not clearly say if he came up with the track idea himself.  So my current assumption is that Sire invented the "Maxwell" top by modifying the Robert's top.

[ta0]

A cheap version of the Maxwell/Sire-Robert top on a video from Tim's toy museum (but Grand Illusions is not selling it):

[Lourens]

Last year I have posted a reaction in this forum about the Maxwell Spinning Top of Ta0 but I have never shared a picture of the top I wrote about. My top is called 'Ptolemy's Top', named after the famous astronomer, geographer and mathematician. I got it as a gift in 1970's from Mary Hillier, an English author of books about antique toys. On page 73-74 (chapter scientific toys) of my book 'The lost Art of Spinning Tops' you find more information.

[jim in paris]

hi all
i found this interesting article with the drawing of a top

with adjustable center of gravity it seems


https://en.wikisource.org/wiki/The_New_Student's_Reference_Work/Top


jim

[Jeremy McCreary]

Excellent article, Jim. You can also fool around with center of mass location with LEGO tops quite easily, but they're nowhere near as cool as Maxwell's metal masterpiece.

Recently learned that Maxwell had been fascinated by tops throughout his life. In addition to being by most accounts the greatest theoretical physicist of the 19th century, he was also a talented experimentalist and often used tops in the lab. For example, he used the "dynamical top" you linked in his important work on rigid body dynamics, where top physics mostly resides.

He also used the top in his hand below to prove (for the first time at age 24) that red, green, and blue (RGB) are the true primary colors when mixing light (as opposed to mixing pigments).  Though best known for his famous equations of electromagnetism, Maxwell was also the father of the modern theory of color vision.



On learning about his color-mixing top, I naturally had to make some of my own. Here, lime and orange mix to yellow instead of brown in accordance with Maxwell's light-mixing rules.




More about LEGO color-mixing tops at http://www.moc-pages.com/moc.php/421944.

[Iacopo]

with adjustable center of gravity it seems

The three vertical screws should be for the dynamic balance, and the horizontal ones for the static balance, but I can't guess why there are so many, three in the horizontal plane would have been enough, I suppose.

[ta0]

hi all
i found this interesting article with the drawing of a top
with adjustable center of gravity it seems
https://en.wikisource.org/wiki/The_New_Student's_Reference_Work/Top
jim

Great find Jim!
I merged this thread with the old (itself merged) Maxwell top thread.

The paper mentioned by the article can be found online here:
https://archive.org/details/scientificpapers01maxw/page/248/mode/2up

This shines a lot of light on why the top is called a Maxwell top. Maxwell read his paper to the Royal Society of Edinmburgh on April 20, 1857. That is about 4 years before the "Polytrope" French paper from Sire. However, Maxwell's paper does not mention the upper track while Sire does. There is still some mystery about who came up with the track idea, but I won't protest anymore about calling it a Maxwell top 

Here is the plate from Maxwell paper:



As described by Maxwell, he wants to be able to have the center of mass at the pivot point, to be able to make all three principal axis the same or different and in that case to be able to determine which has the largest moment of inertia, which one has the lowest and which one is intermediate. In addition he wants to be able to incline the principal axis with respect to the shaft of the top. He says that to accomplish all these things he needs nine adjustments (the screws with heavy heads) but the top has eleven for convenience (using the screw of the shaft and the bob on it).

One of the most interesting things is the colored disc that he adds to find the "invariable" axis of rotation (which is close to the instantaneous axis of rotation). Because it is painted in 4 sectors of different colors he can tell where is the axis at any moment from the color that is not mixed. He can also tell the distance to the shaft using the concentric circles.
Great paper! I need to read it carefully.

Jeremy: your lego tops are really versatile! You seem to have examples for anything!

[Jeremy McCreary]

Iacopo: Taking away all the removable parts on Maxwell's dynamical top would leave something very much like your tops -- at least the ones we've been discussing on the "test" thread. Convergent evolution, or was Maxwell an inspiration?

ta0: Great explanation of Maxwell's dynamical top. Downloaded his paper about it some time ago but never finished reading it.

If my examples weren't made of LEGO, there'd be a lot fewer of them. I'm always on the prowl for connections between tops, science, and art. When I run across something juicy (like Maxwell's color-mixing top), whipping up a LEGO prototype is usually no big deal.

In fact, I'll be starting on a prototype of his dynamical top tonight, thanks to this thread. What a wonderful forum this is!

[Jeremy McCreary]

Louren: Is your book available in English? If so, how do I buy copy?

[Lourens]

Hello Jeremy,
My book is available in English and for members of this forum it is for sure stil available. You find more informatio at my website: www.artofspinningtops.com.
If you have any questions, please let me know and I will be happy to help.
Warm regards, Lourens

[Lourens]

Concidering this discussion (is Maxwell the only one with a 'Maxwell top'-idea): Many scientists in Europe were working on the same theme in the same time. Some of them added new information / research on research already done by other scientists. I know that more people were active on this priciple like:
-Michael Faraday (1791-1867)
-Sir Michael Brewster in 1815
-Joseph Plateau (Belgium 1801-1883)
They all used the spinning top as a way to research light, colors, movement and optical illusions.
Like the Thaumatropes and Phenakistoscope.
At the moment I have little time to give a proper reaction but I hope this helps a little bit.
To be continued ...?

[jim in paris]

hi all ! salut Lourens !
thanx for your input
i knew of Joseph Plateau.....
 in Bruxelles  there is a street "rue Joseph Plateau"
he was a great scientist , passionate with retina persistence

i hope all is well in Hoorn ;--)

jim