[Tom Bishop]

A second set of experiments in a "hidden box" may be helpful, in the case that the experiment always gives random results. But what if they always give the same wrong results?

https://en.wikipedia.org/wiki/Scientific_control

"A scientific control is an experiment or observation designed to minimize the effects of variables other than the independent variable."

It seems difficult doubt that the third container in the three container version of this experiment serves the purpose of the above -- to minimize the effects of variables which may affect the device and act as testament to the underlying hypothesis.

Maybe the curved meniscus always makes the level seem too high. Perhaps the water isn't really level in such devices. It could be that the refraction from going between air and water always affects the results.

In any case, the experiment should be calibrated and controlled for validity.

[AATW]

In any case, the experiment should be calibrated and controlled for validity.

Everyone on here who has ever seen you post knows that if these experiments showed a horizon at eye level you would accept them unquestioningly.

Only because this result does not match your confirmation bias are you flailing around trying to dispute the result - a result which confirms several other methods which people on here have shown and give the same result.

But I look forward to seeing the results of your calibrated and controlled experiments.

[inquisitive]

A second set of experiments in a "hidden box" may be helpful, in the case that the experiment always gives random results. But what if they always give the same wrong or high results?

https://en.wikipedia.org/wiki/Scientific_control

"A scientific control is an experiment or observation designed to minimize the effects of variables other than the independent variable."

It seems difficult doubt that the third container in the three container version of this experiment serves the purpose of the above -- to minimize the effects of variables which may affect the device and act as testament to the underlying hypothesis.

Maybe the curved meniscus always makes the level seem too high. Perhaps the water isn't really level in such devices. It could be that the refraction from going between air and water always affects the results.

In any case, the experiment should be calibrated and controlled for validity.

You could use something like a Leica NA332 which has 1.8mm standard deviation over 1km and comes with a calibration certificate.

[Tom Bishop]

In any case, the experiment should be calibrated and controlled for validity.

Everyone on here who has ever seen you post knows that if these experiments showed a horizon at eye level you would accept them unquestioningly.

Only because this result does not match your confirmation bias are you flailing around trying to dispute the result - a result which confirms several other methods which people on here have shown and give the same result.

But I look forward to seeing the results of your calibrated and controlled experiments.

A version of the experiment was already performed with a third calibration chamber. The device was unable to be calibrated, suggesting that it is invalid in premise.

[stack]

In any case, the experiment should be calibrated and controlled for validity.

Everyone on here who has ever seen you post knows that if these experiments showed a horizon at eye level you would accept them unquestioningly.

Only because this result does not match your confirmation bias are you flailing around trying to dispute the result - a result which confirms several other methods which people on here have shown and give the same result.

But I look forward to seeing the results of your calibrated and controlled experiments.

A version of the experiment was already performed with a third calibration chamber. The device was unable to be calibrated, suggesting that it is invalid in premise.

Bobby has a pretty well "calibrated" version and the eye-level to horizon difference seems quite significant:

[Tom Bishop]

Doesn't look lined up to me.



It appears to be another piece of evidence that these devices are unable to be calibrated.

[inquisitive]

Doesn't look lined up to me.



It appears to be another piece of evidence that these devices are unable to be calibrated.

The accuracy is well within that needed to show the horizon is below the level of the instrument.  Do you have an alternative design?

[Tom Bishop]

What accuracy? The device needs to be able to be calibrated before one can say how accurate or close the method is.

The device and underlying theory may be totally off in application. It's making a lot of assumptions about perspective, water tension, refraction, etc. The fact that it can't be calibrated shows the issue. We need a way to gauge how accurate it is.

[stack]

The device may be totally off. The fact that it can't be calibrated shows the issue.

Or maybe spot on.

One guy has a problem "calibrating" his device, perhaps for the any of the myriad reasons already mentioned, and you claim that it's a fact that these devices can't be calibrated? All it takes for Zetetics is one guy, one experiment? If so, good to know that's how you science.

[Tom Bishop]

This experiment has not been proven to be valid or accurate, or have any bearing on anything at all. It is not used in surveying or for any purpose. The principles need to be demonstrated.

Yes, it does take only one experiment to discredit the device.

The third chamber acted as a control. Which means that all other experiments of that nature were uncontrolled.

[inquisitive]

A second set of experiments in a "hidden box" may be helpful, in the case that the experiment always gives random results. But what if they always give the same wrong or high results?

https://en.wikipedia.org/wiki/Scientific_control

"A scientific control is an experiment or observation designed to minimize the effects of variables other than the independent variable."

It seems difficult doubt that the third container in the three container version of this experiment serves the purpose of the above -- to minimize the effects of variables which may affect the device and act as testament to the underlying hypothesis.

Maybe the curved meniscus always makes the level seem too high. Perhaps the water isn't really level in such devices. It could be that the refraction from going between air and water always affects the results.

In any case, the experiment should be calibrated and controlled for validity.

You could use something like a Leica NA332 which has 1.8mm standard deviation over 1km and comes with a calibration certificate.

Tom, use this.

[stack]

This experiment has not been proven to be valid or accurate, or have any bearing on anything at all. It is not used in surveying or for any purpose. The principles need to be demonstrated.

Sure it's used for surveying purposes and the principles have been demonstrated since the greeks.

"A water level; Greek: Aλφαδολάστιχο or (υδροστάθμη) [Alfadolasticho] is a device used for matching elevations of locations that are too far apart for a spirit level to span."

https://en.wikipedia.org/wiki/Water_level_(device)

Some good old time agricultural surveying use:

Yes, it does take only one experiment to discredit the device.

Interesting.

The third chamber acted as a control. Which means that all other experiments of that nature were uncontrolled.

Bobby's had a third chamber.

[Tom Bishop]

The video you posted isn't the same experiment at all. Where do they attempt to align the water levels with something in the distance?

Bobby's water levels did not line up. According to your hypothesis they should line up. Therefore the hypothesis or application is incorrect.

[stack]

The video you posted isn't the same experiment at all. Where do they attempt to align the water levels with something in the distance?

You obviously didn't watch the video. They align them by getting each tube to the same mark as they are measuring the slope of the hill. Same concept.

Bobby's water levels did not line up. According to your hypothesis they should line up. Therefore the hypothesis or application is incorrect.

Sorry, he used 4, there's one on the camera too. And here's that Bobby experiment with no water tubes, if you like that method better.

[Tom Bishop]

Unfortunately all of the water levels in Bobby's experiment were not level.



This viewer suggested that a control was needed verify that all sighting devices were level and in-line. Since they did not match up, they must not be.

[stack]

Unfortunately all of the water levels in Bobby's experiment were not level.



This viewer suggested that a control was needed verify that all sighting devices were level and in-line. Since they did not match up, they must not be.

Great, so you're anti water level. No water level in the string box. Seems to show the same disparity between eye-level and horizon as the water level experiment does.

[QED]

A second set of experiments in a "hidden box" may be helpful, in the case that the experiment always gives random results. But what if they always give the same wrong results?

https://en.wikipedia.org/wiki/Scientific_control

"A scientific control is an experiment or observation designed to minimize the effects of variables other than the independent variable."

It seems difficult doubt that the third container in the three container version of this experiment serves the purpose of the above -- to minimize the effects of variables which may affect the device and act as testament to the underlying hypothesis.

Maybe the curved meniscus always makes the level seem too high. Perhaps the water isn't really level in such devices. It could be that the refraction from going between air and water always affects the results.

In any case, the experiment should be calibrated and controlled for validity.

“To minimize the effects of variables which may affect the device and act as testament to the underlying hypothesis.”

No this would be leading the data. A control isolates a variable from the measurement.

But yes, perhaps the water isn’t really level in those devices, etc etc, and perhaps you just are fabricating complaints because you do not like the outcome.

You see, when an experiment is performed, and another believes there to be a confounding variable. Then that person inherits a burden of proof: to demonstrate that variable is really confounding. THAT is the scientific method.

One does not get to pull variables out of his ass and insist that the experimenters atone for them before the results are believed. No. You must demonstrate it. And showing a picture with crudely drawn sight lines does not meet any scientific standard I have ever seen. It is something children do.

[Tom Bishop]

The matter has already been impeached. The inability to calibrate the three chamber version of the device is direct evidence that the water is not level.



Last year a caged water device was built by a member of our forums, which showed that the alignment of the liquid in the device is susceptible to error. It was seen that the liquid did not align and that water did not find its level.

https://forum.tfes.org/index.php?topic=9492.280



The water levels did not line up to each other in relation to the plumb line.

The burden to show these devices as valid is absolutely on those who champion it.

A small error in the foreground can cause a very large error many miles away.



Again, if you are championing these devices then it is your responsibility to show that they are accurate. Ignoring direct evidence is not acceptable.

Surveying is not an accurate science by its very nature. The idea that someone can create surveying tools without the need to calibrate it or test it for accuracy is quite rediculous.

http://whistleralley.com/surveying/theoerror/

As any surveyor should understand, all measurements are in error. We try to minimize error and calculate reasonable tolerances, but error will always be there. Not occasionally; not frequently; always. In the interest of more accurate measurements, we look for better instruments and better procedures.
—Paul Kunkel

Are you a surveyor? Do you know better than the surveyors who tell us that surveying is always in error? Are we to believe that amateurs created superior surveying equipment that can accurately test the horizon, the furthest thing that can be tested in surveying?

No, that is absurd. Once again, the burden is entirely on those who champion the device to demonstrate its validity.

[stack]

Wow, six pages in and we've landed on asking if someone is a surveyor coming from someone who I assume is not a surveyor. Fetching retort.

So the question in the OP, actually the title of the OP is, "What's the best tool for measuring eye level?"

So to FE, the society perhaps, what is the best tool for measuring eye level? Sounds like according to you, nothing is. Am I correct or could you actually answer the OP?

[Tom Bishop]

Samuel Birley Rowbotham studied that very topic in his work Earth Not a Globe. Take a look at his eye level and horizon experiments in Chapter 2, as well as his theodolite experiments.