The Bedford Level Experiment

In the link I gave earlier, showing to you that Wallace was not a flat earther, it states that he used a telescope.

http://www.wku.edu/~smithch/wallace/S162-163.htm

If you don't fancy reading it, here's a short quote mentioning the telescope "2. Mr Carpenter objects to the value of the view in the large telescope, "because it showed but two points, when a comparison had to be instituted between three;" but he omits to state that the telescope itself was placed accurately at the third point, just as was the spirit-level telescope--to the view shown by which he makes no such objection."

I'm sure any other scientists who conducted the experiment would have used a telescope too, and I think you feel that way too really.

Quote from: GazMcB on December 05, 2007, 11:44:41 AM

In the link I gave earlier, showing to you that Wallace was not a flat earther, it states that he used a telescope.

http://www.wku.edu/~smithch/wallace/S162-163.htm

If you don't fancy reading it, here's a short quote mentioning the telescope "2. Mr Carpenter objects to the value of the view in the large telescope, "because it showed but two points, when a comparison had to be instituted between three;" but he omits to state that the telescope itself was placed accurately at the third point, just as was the spirit-level telescope--to the view shown by which he makes no such objection."

I'm sure any other scientists who conducted the experiment would have used a telescope too, and I think you feel that way too really.

bishop has mysteriously shut up or conveniently forgotten about this thread.

Wait, what was the point of that, again?

The diagram and the discussion about it.

Right, Rowbotham assumed there were not outside variables, such as:
- refraction
- the level of the canal.
- his height, which would change the location of the tangent.

...

The only modification which can be made in the above calculations is the allowance for refraction, which is generally considered by surveyors to amount to one-twelfth the altitude. of the object observed. If we make this allowance, it will reduce the various quotients so little that the whole will be substantially the same. Take the last case as an instance. The altitude of the light on Cape Bonavista, Newfoundland, is 150 feet, which, divided by 12, gives 13 feet as the amount to be deducted from 491 feet, making instead 478 feet, as the degree of declination.

Many have urged that refraction would account for much of the elevation of objects seen at the distance of several miles. Indeed, attempts have been made to show that the large flag at the end of six miles of the Bedford Canal (Experiment 1, fig. 2, p. 13) has been brought into the line of sight entirely by refraction. That the line of sight was not a right line, but curved over the convex surface of the water; and the well-known appearance of an object in a basin of water, has been referred to in illustration. A very little reflection, however, will show that the cases are not parallel; for instance, if the object (a shilling or other coin) is placed in a basin without water there is no refraction. Being surrounded with atmospheric air only, and the observer being in the same medium, there is no bending or refraction of the eye line. Nor would there be any refraction if the object and the observer were both surrounded with water. Refraction can only exist when the medium surrounding the observer is different to that in which the object is placed. As long as the shilling in the basin is surrounded with air, and the observer is in the same air, there is no refraction; but whilst the observer remains in the air, and the shilling is placed in water, refraction exists. This illustration does not apply to the experiments made on the Bedford Canal, because the flag and the boats were in the same medium as the observer--both were in the air. To make the cases parallel, the flag or the boat should have been in the water, and the observer in the air; as it was not so, the illustration fails. There is no doubt, however, that it is possible for the atmosphere to have different temperature and density at two stations six miles apart; and some degree of refraction would thence result; but on several occasions the following steps were taken to ascertain whether any such differences existed. Two barometers, two thermometers, and two hygrometers, were obtained, each two being of the same make, and reading exactly alike. On a given day, at twelve o'clock, all the instruments were carefully examined, and both of each kind were found to stand at the same point or figure: the two, barometers showed the same density; the two thermometers the same temperature; and the two hygrometers the same degree of moisture in the air. One of each kind was then taken to the opposite station, and at three o'clock each instrument was carefully examined, and the readings recorded, and the observation to the flag, &c., then immediately taken. In a short time afterwards the two sets of observers met each other about midway on the northern bank of the canal, when the notes were compared, and found to be precisely alike--the temperature, density, and moisture of the air did not differ at the two stations at the time the experiment with the telescope and flag-staff was made. Hence it was concluded that refraction had not played any part in the observation, and could not be allowed for, nor permitted to influence, in any way whatever, the general result.

In may, the author delivered a course of lectures in the Mechanics' Institute, and afterwards at the Rotunda, in Dublin, when great interest was manifested by large audiences; and he was challenged to a repetition of some of his experiments--to be carried out in the neighbourhood. Among others, the following was made, across the Bay of Dublin. On the pier, at Kingstown Harbour, a good theodolite was fixed, at a given altitude, and directed to a flag which, earlier in the day, had been fixed at the base of the Hill of Howth, on the northern side of the bay. An observation was made at a given hour, and arrangements had been made for thermometers, barometers, and hygrometers--two of each--which had been previously compared, to be read simultaneously, one at each station. On the persons in charge of the instruments afterwards meeting, and comparing notes, it was found that the temperature, pressure, and moisture of the air had been alike at the two points, at the time the observation was made from Kingstown Pier. It had also been found by the observers that the point observed on the Hill of Howth had precisely the same altitude as that of the theodolite on the pier, and that, therefore, there was no curvature or convexity in the water across Dublin Bay. It was, of course, inadmissible that the similarity of altitude at the two places was the result of refraction, because there was no difference in the condition of the atmosphere at the moment of observation.

Quote from: Trekky0623 on December 13, 2007, 10:08:36 AM

Right, Rowbotham assumed there were not outside variables, such as:
- refraction
- the level of the canal.
- his height, which would change the location of the tangent.

The level of the canal does not matter If the earth were a globe all standing water must form an arc of a circle.

Terrestrial Refraction is a decent copout, but Dr. Samuel Birley Rowbotham accounts for terrestrial refraction in Experiment 9 of Earth Not a Globe:

both have been debunked as fiction.

Quote from: cpt_bthimes on December 13, 2007, 12:37:06 PM

both have been debunked as fiction.

I am curious to see where, because I hardly consider a thread such as this one to be evidence.