FOOTNOTES:
[268] Catholic World, November, 1873, page 187.
[269] This limitation is necessity. A stone thrown up vertically soon loses its vis viva without compensation. The case is one in which there is no impact. An imponderable body, as luminiferous æther, if it forms, as it is most probable, an unresisting medium, acquires vis viva without interfering with the vis viva of the celestial bodies.
[270] Physicists sometimes give the name of action and reaction to the opposite efforts of two conflicting bodies. But, properly speaking, the two efforts are two actions; the reaction only begins at the end of compression, and takes place mostly within each body separately.
[271] Balfour Stewart, Lessons in Elementary Physics, P. 101.
[272] I say natural accidents. The species of bread and of wine in the Holy Eucharist are supernatural accidents, and have no less active power than the substances themselves. The reason is that they imply in their constitution "the act and the activity of the substance"—actum et vim substantiæ—as S. Thomas teaches, and "all that which belongs to matter"—omne illud quod ad materiam pertinet. See the Summa Theol., p. 3, q. 77, a. 5.
[273] In the New American Cyclopædia, edited in 1863 (v. Mechanics), after the statement that "to overcome all the inertia of a body moving with a certain velocity, or to impress on it at rest such a velocity, the same whole quantity of action must in either case be exerted and expended upon the body," we are given to understand that this quantity is equal to half the product of the mass of the body into the square of the given velocity. From what we have just shown, it is evident that this conclusion is false.
LATE HOME.
Mother, I come! Long have thine arms, outspread
In mercy and maternal majesty,
Been waiting to receive me. Long have I
Heard thy low, summoning voice in wistful dread:
A truant child, who yearned, yet feared, to tread
The threshold of its home, while still on high
Blazed the broad sun within the noonday sky;
But, when the shadows of the evening came,
And darkness fell, was fain to seek the flame
Of its own hearthstone and its mother dear,
And meet her greeting, loving, if severe,
Her frown, which could not hide the secret tear,
Her gaze compassionate, though sad and stern,
Her fond forgiveness of that late return.