Go to National Library of New Zealand Te Puna Mātauranga o Aotearoa
Volume 14, 1881
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1.

“On a Fundamental Error in Dynamics, the Theory of Gravitation, and the Nebular Hypothesis,” by Victor Falkner.

Abstract

The paper dealt with Newton's explanation of Kepler's laws and that part of the nebular hypothesis that hinges on it. The writer contended that dynamics was essentially an experimental and inductive science, and that little reliance could be placed on the results of deduction in it. He

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argued that such an important problem as that involved in the Newtonian theory should never have been accepted as proved without experimental demonstration. After entering fully into Newton's and Laplace's theories, Mr. Falkner stated that the hypotheses assumed that the path of a body propelled in free space by an impulse, or travelling tangentially at uniform velocity, and attracted to a centre with a force varying inversely as the square of its distance from that centre, is an ellipse of which the attracting centre is in one focus (or a similar conic section), and an orbit similar to the planetary and cometary. This assumption he denied, and affirmed that the path of a body subject to an impulse, or its equivalent, moving in free space, and subject to any central force, is such a figure that the attracting point is in its centre, or at the intersection of its axes. He supported this affirmation by viewing the assumption in its extremes, and endeavoured to show it as contradicting the axiom that “action and re-action are contrary and equal,” and explaining his own conclusions and their agreement with the results of his experiments. He then reviewed current graphic methods, and pointed out where he considered the errors had been made, and explained and discussed the apparatus.

Mr. M. Chapman contended that the matter was not one that could be dealt with by experiment, but must be dealt with by mathematical investigation. He could not believe in Mr. Falkner's results for a single instant.

The Chairman expressed a hope that Mr. Falkner would not upset the “Nautical Almanack.”

Mr. Falkner then advanced the statement that astronomy really rested on Kepler's laws, and not on Newton's explanations of them, the most important of which, like so many previous problems in dynamics solved deductively, when put to the test proved quite erroneous.

2.

“New Cuttle Fish,” by T. W. Kirk. (Transactions, p. 283).