CHAPTER XVI
[1] Thales had guessed that water was the primal element from which all had been derived; Anaximenes guessed air; Heraclitus fire; Pythagoras held that number was the essence of all things; Empedocles thought that fire and heat, accompanied by "indestructible forces," formed the basis; Xenophanes had guessed air, fire, water, and earth, and had worked out a complete scheme of creation. For an interesting discussion of these early attempts to explain creation, see J. W. Draper, History of the Intellectual Development of Europe, vol. 1, chap. iv.
[2] Among the treatises by him accepted as genuine are On Airs, Waters, and Places; On Epidemics; On Regimen in Acute Diseases; On Fractures; and On Injuries of the Head.
[3] For example, Hippocrates had held that the human body contains four "humors"—blood, phlegm, yellow bile, and black bile—and that disease was caused by the undue accumulation of some one of these humors in some organ, which it was the business of the physician to get rid of by blood- letting, blistering, purging, or other means.
[4] From a collection of doggerel rhymes put out by two pastors and doctors of theology at Basle, in 1618, by the names of Grassner and Gross, to interpret the orthodox theory of comets to peasants and school children.
[5] "The earth is a sphere, situated in the center of the heavens; if it were not, one side of the heavens would appear nearer to us than the other, and the stars would be larger there. The earth is but a point in comparison to the heavens, because the stars appear of the same magnitude and at the same distance inter se, no matter where the observer goes on the earth. It has no motion of translation…. If there were a motion, it would be proportionate to the great mass of the earth and would leave behind animals and objects thrown into the air. This also disproves the suggestion made by some, that the earth, while immovable in space, turns round on its own axis." (Ptolemy, Digest of argument of Book 1 of the Almagest.)
[6] In the dedicatory letter Copernicus states that he had had the completed manuscript in his study for thirty-six years, and published it now only on the urging of friends.
[7] To secure the greatest possible accuracy he constructed a wooden outdoor quadrant some ten feet in radius, with a brass scale, thus permitting readings to a fraction of an inch.
[8] "The current view was that comets were formed by the ascending of human sins from the earth, that they were changed into a kind of gas, and ignited by the anger of God. This poisoned stuff then fell down on people's heads, causing all kinds of mischief, such as pestilence, sudden death, storms, etc." (Dryer, J. L. E., Tycho Brahe.)
[9] "For over fifty years he was the knight militant of science, and almost alone did successful battle with the hosts of Churchmen and Aristotelians who attacked him on all sides—one man against a world of bigotry and ignorance. If then… when face to face with the terrors of the Inquisition he, like Peter, denied his Master, no honest man, knowing all the circumstances, will be in a hurry to blame him." (Fahie, J. J., Galileo, His Life and Work.)
[10] See Routledge, R., A Popular History of Science, pp. 135-36, for a good digest of Bacon's inductive investigation, as a result of which he arrived at the conclusion that "Heat is an expansive bridled motion, struggling in the small particles of bodies."
[11] Bacon himself died a victim of one of his inductive experiments. Wishing to try out his theory that cold would prevent or retard putrefaction, he killed a chicken, cleaned it, and packed it in snow. In so doing he contracted a cold which caused his death.