65. By guessing the height and speed of a steamer Rowbotham thought that the steamer would have disappeared from view sooner on a spherical Earth

“Also Quoting Dr. Rowbotham, “On the shore near Waterloo, a few miles to the north of Liverpool, a good telescope was fixed, at an elevation of 6 feet above the water. It was directed to a large steamer, just leaving the River Mersey, and sailing out to Dublin. Gradually the mast-head of the receding vessel came nearer to the horizon, until, at length, after more than four hours had elapsed, it disappeared. The ordinary rate of sailing of the Dublin steamers was fully eight miles an hour; so that the vessel would be, at least, thirty-two miles distant when the mast-head came to the horizon. The 6 feet of elevation of the telescope would require three miles to be deducted for convexity, which would leave twenty-nine miles, the square of which, multiplied by 8 inches, gives 560 feet; deducting 80 feet for the height of the main-mast, and we find that, according to the doctrine of rotundity, the mast-head of the outward bound steamer should have been 480 feet below the horizon. Many other experiments of this kind have been made upon sea-going steamers, and always with results entirely incompatible with the theory that the earth is a globe.”

None of the required measurements are known to make this a proof of anything.

The obvious point here is that Rowbotham's account has he steamer disappearing over the horizon.  That there is a horizon to disappear over is evidence that the Earth is spherical.  The issue of how far away the steamer was when it disappeared over the horizon o are only affected by the size of the globe and the effects of refraction.

The larger the size of the globe, the further away the horizon will be.
The larger the effect of refraction, the nearer the horizon will be.

So straight away we can see that this observation in itself not a proof of a flat Earth, but only that Earth may be larger than scientists believe.

Secondly, whatever the normal speed of steamers, Rowbotham had no way of knowing what speed that particular steamer was travelling at at that particular time or the height of that particular mast.

On a spherical Earth an observer with eye level at 6 feet above sea level, a steamer with its mast reaching 80 feet would disappear over the horizon at 14 miles if we do not take refraction into account.

Given the lack of proper measurements of observer elevation, ship height, ship distance and atmospheric conditions this historic observation does not prove anything.


< Prev  61-70 Next >