William John Macquorn Rankine Quotes

13 Sourced Quotes

Discrepancy between theory and practice, which in sound physical and mechanical science is a delusion, has a real existence in the minds of men; and that fallacy, through rejected by their judgments, continues to exert and influence over their acts.

William John Macquorn Rankine
The hypothesis of molecular vortices is defined to be that which assumes — that each atom of matter consists of a nucleus or central point enveloped by an elastic atmosphere, which is retained in its position by attractive forces, and that the elasticity due to heat arises from the centrifugal force of those atmospheres revolving or oscillating about their nuclei or central points.
According to this hypothesis, quantity of heat is the vis viva of the molecular revolutions or oscillations.

William John Macquorn Rankine
It is possible to express the laws of thermodynamics in the form of independent principles, deduced by induction from the facts of observation and experiment, without reference to any hypothesis as to the occult molecular operations with which the sensible phenomena may be conceived to be connected; and that course will be followed in the body of the present treatise. But, in giving a brief historical sketch of the progress of thermodynamics, the progress of the hypothesis of thermic molecular motions cannot be wholly separated from that of the purely inductive theory.

William John Macquorn Rankine
A hypothetical theory is necessary, as a preliminary step, to reduce the expression of the phenomena to simplicity and order before it is possible to make any progress in framing an abstractive theory.

William John Macquorn Rankine
This law (regarding the theoretical efficiency of heat engines by Mr. Joule), and the law of the maximum efficiency of heat engines, are particular cases of a general law which regulates all transformation of energy, and is the basis of the Science of Energetics.

William John Macquorn Rankine
The law of the conservation of energy is already known, viz. that the sum of the actual and potential energies in the universe is unchangeable.

William John Macquorn Rankine
Hypothesis Of Molecular Vortices. In thermodynamics as well as in other branches of molecular physics, the laws of phenomena have to a certain extent been anticipated, and their investigation facilitated, by the aid of hypotheses as to occult molecular structures and motions with which such phenomena are assumed to be connected. The hypothesis which has answered that purpose in the case of thermodynamics, is called that of "molecular vortices," or otherwise, the "centrifugal theory of elasticity.

William John Macquorn Rankine
An essential distinction exists between two stages in the process of advancing our knowledge of the laws of physical phenomena; the first stage consists in observing the relations of phenomena, whether of such as occur in the ordinary course of nature, or of such as are artificially produced in experimental investigations, and in expressing the relations so observed by propositions called formal laws. The second stage consists in reducing the formal laws of an entire class of phenomena to the form of a science; that is to say, in discovering the most simple system of principles, from which all the formal laws of the class of phenomena can be deduced as consequences.

William John Macquorn Rankine
Now integrate L with respect to dt, (t Standing for time and persuasion); Then, between proper limits, 'tis easy to see, The definite integral Marriage must be — (A very concise demonstration).

William John Macquorn Rankine
The words 'theory' and 'practice' are of Greek origin; they carry our thoughts back to the ancient philosophers by whom they were contrived, and by whom they were also contrasted and placed in opposition, as denoting two mutually conflicting and mutually inconsistent ideas.... [this fallacy] based on a double system of natural laws retarded for centuries the development of physical science, notably mechanics.

William John Macquorn Rankine
Thus it is that the commonest objects are by science rendered precious; and in like manner the engineer or the mechanic, who plans and works with understanding of the natural laws that regulate the results of his operations, raise to the dignity of a Sage.

William John Macquorn Rankine
Let x denote beauty, y manners well-bred, z fortune (this last is essential), Let L stand for love — our philosopher said — Then L is a function of x, y and z Of the kind that is known as potential.

William John Macquorn Rankine
A party of astronomers went measuring of the earth, And forty million meters they took to be its girth; Five hundred million inches, though, go through from pole to pole; So lets stick to inches, feet, and yards, and the good old three-foot rule.

William John Macquorn Rankine