But, despite the persecution of Bacon and the defection of those who ought to have followed him, champions of natural science and the experimental method arose from time to time during the succeeding centuries. We know little of them personally. Our main knowledge of their efforts is derived from the efforts of their opponents and persecutors.
In 1317 Pope John XXII. issued his bull Spondent Pariter, nominally leveled at the alchemists, but really dealing a terrible blow at the beginnings of the science of chemistry.
In 1380 Charles V. of France carried out the same policy, and even forbade the possession of furnaces and apparatus necessary for chemical processes. Under this law the chemist John Barillon, for possessing chemical furnaces and apparatus, was thrown into prison, and it was only by the greatest effort that his life was saved.
In 1404 Henry IV. of England issued a decree of the same sort; and in 1418 the republic of Venice followed the example of pope and kings. But champions of science still pressed on. Antonio de Dominis relinquishes his archbishopric of Spalatro, investigates the phenomena of light, and dies in the clutches of the Inquisition. [102]
Pierre de la Ramée stands up against Aristotelianism at Paris. A royal edict, sought by the Church, stopped his teaching, and the massacre of St. Bartholomew ended his life.
Somewhat later, John Baptist Porta began his investigations. Despite many absurdities, his work was most fruitful. His book on meteorology was the first in which sound ideas were broached. His researches in optics gave the world the camera obscura, and, possibly, the telescope. In chemistry he seems to have been the first to show how to reduce the metallic oxides, and thus to have laid the foundation of all those industries based upon the staining and coloring of glass and enamels; and, last of all, he did much to change natural philosophy from a "black art" to a vigorous open science. He encountered the same old policy of conscientious men. The society founded by him for physical research, "I Secreti," was broken up, and he was summoned to Rome and censured. [103]
In 1624 some young chemists of Paris, having taught the experimental method and cut loose from Aristotle, the Faculty of Theology besets the Parliament of Paris, and the Parliament prohibits this new chemical teaching under penalty of death. [104]