Merseburg wheel part

[rasselasss]

Ovyyus,if we think of Archimedes pulling a heavy laden boat into dock single handedly with a multiplication of pulleys ...there has to be mileage in your theory.

[rlortie]

I do not believe that the rope wound up on the axle for a full story high length. I am inclined to believe as Fletcher once pointed out, the axle was used as a "windlass" with maybe two wraps on the axle.

If a four part line was used the rope would be rather lengthy, a ten foot raise would require over 50 feet of rope.

My reasoning for this is quite simple; how would one lower and raise the box of bricks without stopping the wheel and changing directions. With a windless all you have to do is release tension on the tag end of the rope. The box of brick would then return to the ground.

Applying tension would not only tighten the rope around the axle, but also give a false reading of the force applied by the machine as the person pulling on the rope would be compensating part of the burden.

(In Jest)
I some times wonder why we get on these obscure topics. My college "Logic" professor taught me that if it does not make the wheel run 'gooder' then there ain't no need to discuss it. :-)

Ralph

[ovyyus]

Ralph, your speculation seems unnecessary given the Merseburg Wheel drawing already depicts the method used to wind up/down the rope from the axle.

Taken from the drawing, the length of axle available to wind rope is about 18 inches. If 1/4 inch rope is used then 72 winds of rope is possible. With each wind being about 19 inches of rope, this gives a total of 114 feet of rope able to be wound onto the axle. If the lift height was 14 feet and a 4 x pulley reduction is used then about 56 feet of rope would need to be wound onto the axle, which would only take up about half the 18 inches of available axle space.

[rlortie]

Bill,

It also depicts stampers floating in mid air outside their lifter pockets.
It depicts pendulums that were not said to be there.
The pendulums that are there, do not have the same pivot arrangement,
The rope is not in "lead" with the pulley.

Need I say more to make a simple speculation? The depiction, IMO is nothing more than an etching for public viewing and holds little specifications of the actual machine.

OK! you pulled an edit on me! ;-) You are now saying that the wheel had to be stopped and direction reversed to lower the box of bricks, each time it reached the top pulley.

Ralph

[jim_mich]

Wolff reported the lifting of the load of 6 whole bricks (70 lbs) as being quite slow due to a 4 x pulley reduction (see attached 4 x pulley reduction diagram).

No bill, Wolff said, "At the moment it can lift a weight of sixty pounds, but to achieve this the pulley had to be reduced more than four times, making the lifting quite slow."
Note that he used the single word 'pulley', and he used 'more than". If it were a block and tackle, then there would be more than a single pulley and the exact reduction is very simple to know, just count the number of ropes supporting the weight.

On page 192 of John Collin's Das Triumphirende PERPETUUM MOBILE Orffyreanum, Bessler wrote...

For this concept, my ‘principle of excess weight’, is NOT just -snip-
It is, however, an incontestable truth that my much-mentioned Wheel deserves not only the name of the long-sought Perpetual Motion, but also, just as much, the name (Perpetual) Mover; since it is an example of one of the best-known of all mechanical appliances, namely a peritrochium.

Definition:

peritrochium: The wheel which, together with the axle, forms the axis in peritrochio, which see under {Axis}.

{Axis in peritrochio}, the wheel and axle, one of the mechanical powers.

Fact:
Bessler does not show any block and tackle.

Fact:
A 20 second lift is a slow lift.

Fact:
The wheel itself was a pulley reduction machine, in other words a peritrochium where a large wheel turns a small axle that lifts the load.

Fact:
A block and tackle has a fixed ratio, not a 'more than' reduction.

Fact:
It cannot be known that a statement saying 'the pulley had to be reduced more than four times' implies a block and tackle. It can just as easily imply the peritrochium that Bessler talks about.

Peritrochium was a common word during Bessler's time. It has become obsolete in out time.

A peritrochium was a common method of using a pulley arrangement to reduce speed and thus gain lifting force. The small pulley is the axle. The large pulley is the wheel.

I strongly object to the continual insinuation that Bessler's wheel was weak and thus could only lift about 70 lbs by adding a block and tackle with a 'more than' four times reduction, thus making the Merseburg wheel capable of lifting only about 14 lbs instead of the witnessed 60 lbs.

[ovyyus]

Jim, you did not address the issue of the handle. If the wheel was as powerful as you think then how was the handle used to stop it?

Also, the ratio of wheel radius to axle radius is 24:1. I doubt Wolff would refer to this as a 'more than' 4:1 pulley reduction.

[rasselasss]

Would it be possible in the orignal translation of errors. ...just a thought...stopping handle ,lifting handle etc.

[jim_mich]

A 11.15 foot wheel with a 6 inch axle and a 1/4 inch rope give a peritrochium ratio of about 22 to 1.

"reduce more than four times"

Reduce mean simply to make smaller. You cut it in half.
You need to think like workmen 300 years ago.

If you reduce something once, it become 1/2, or a ratio of 1:2
If you reduce something two times, it becomes 1/2/2, or a ratio of 1:4
If you reduce something three times, it becomes 1/2/2/2, or a ratio of 1:8
If you reduce something four times, it becomes 1/2/2/2/2, or a ratio of 1:16
If you reduce something five times, it becomes 1/2/2/2/2/2, or a ratio of 1:32

Bessler's peritrochium wheel had a reduction of between 4 and 5 times.

[rlortie]

"You need to think like workmen 300 years ago."

Ok! I am a "hod" carrier and i am on strike, Bessler's machine of lifting brick is threatening my livelyhood! :-)

[daxwc]

In an age of no electric or gas motors it is hard to determine what is a slow lift means, but my own opinion it is more than 20 sec.

Hard to believe Wolff was wrong in his assessment; meaning he would not have said "At the moment it can lift a weight of sixty pounds, but to achieve this the pulley had to be reduced more than four times, making the lifting quite slow", unless the 60 pounds lift was not a straight up lift and a mechanical advantage was being used. The whole reason he says it is to bring to your attention that the wheel is underpowered and not actually lifting 60lbs.

[ovyyus]

Jim, that certainly seems like a unique take on pulley reduction and I'd like to hear of any 18th century instances of that method of calculating pulley reduction ratio.

You need to think like workmen 300 years ago.

Wolff was not a 'workman'.

I strongly object to the continual insinuation that Bessler's wheel was weak...

I'm sorry about that, Jim. I just want to get to the bottom of the issue, one way or the other. It would be easier if the data wasn't so conflicted. On the one hand Bessler presented his wheel as being powerful and practical, he wanted to sell it. On the other hand we have some eyewitness reports that appear to contradict Bessler's marketing statements. We also have wheel descriptions, such as the depicted stopping handle, odd loaded/unloaded wheel speed reports, reduction pulley reports, etc, that just don't add up.

Wolff and Leibniz both said that unless Bessler's wheel could be somehow improved then it was of little practical value because it's power was so limited. Surely they would not have taken that view if the wheel truly could lift a 70 lb box of bricks to a height of 14 feet in just 12 seconds.

[barksalot]

Rasselasss, The part in question is rather over sized to be a rope stop or guide. The angle the rope winds up on the axle looks to me to be pulling away from the wheel and would after making contact start to track back towards the supports within a few revolutions.

Unless he was planing on it tracking back and forth a lot to completely utilize that size then there would definitely need to be another stop or guide on the other side also.


All

The Kassel wheel does not show any evidence of a handle so maybe he realized it was not needed or that it was a bad idea (dangerous).

I think he referred to his machine as a model, to me that means it really needed more engineering to be a really useful device.

[daxwc]

Karl must have had a reason for not pursuing purchasing Bessler’s wheel himself. The only reason that makes sense, other than fraud, is that it was underpowered and he didn’t see any practical industrial use for it. Therefore Karl became more interested in Papin’s invention.

If Karl's attestment is ever translated and uploaded we might find some clues as to what he thought on the power.

[jim_mich]

to achieve this the pulley had to be reduced more than four times, making
the lifting quite slow.

Read this statement very very carefully!

To achieve this [the lifting of the 60 pounds]

the pulley [not the ratio, but the size of the pulley, the single pulley, not a block and tackle containing multiple pulleys]

had to be reduced [made smaller relative to something else]

more than [a non-precise value greater than the value presented, but less than the next larger value that could be presented]

[a factor of] four times.

If you fold [in other words you reduce] a handkerchief four times, what size does it become relative to its original size? The handkerchief reduced [folded] four times becomes 1/16th its original size. Folded again it becomes 1/32 its original size.

Wolff was saying that the pulley of the wheel, in other words the axle shaft of the peritrochium, which is called the pulley of the peritrochium, was reduced, in other words made smaller than the wheel, and that this reduction was more than four times but less than five times, else he could have said reduced five times.

Reduce something once, and it becomes 1/2 size. Reduce it twice, its 1/4 size. Reduce it three times, its 1/8 size. Reduce it four times, its 1/16 size. Reduce it once more and it becomes 1/32 size. But reduce it more then four times but less than five times and it becomes about half way between, at about 1/24 size, which is as close as we will ever know to the value of Bessler's peritrochium wheel.

You guys are so narrow minded, that you don't let your mind expand to understand a slightly different ways of saying things. Instead you maintain that there is contradiction when there is no contradiction when you understand the true meaning behind the words written 300 years ago.

[ovyyus]

Jim, how is it that you can understand the specific 'true meaning' behind words written 300 years ago while only reading an English translation/interpretation of them? How do you know that Wolff didn't mean pulling, ie: the pulling had to be reduced more than four times? Perhaps Stewart or John could help clarify Wolff's description?

I fail to see the relevant connection between folding a handkerchief and mechanical pulley reduction ratio. If you could provide some instance where mechanical pulley reduction is used in the terms you claim Wolff used it then that would help support your case. I've never heard of such a thing.

Jim, you still did not address the issue of the axle handle. If the wheel was as powerful as you prefer to believe then how did the operator use that little handle to stop it?