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announced as articles of scientific belief but also followed in practice. It is clear, therefore, that modern methods of observational and experimental science were not founded by the works of Francis Bacon. Before his day, Tycho Brahe had gone to the heavens for his astronomical facts instead of to Greek philosophy, and had earnestly urged his pupil Kepler “to lay a solid foundation for his views by actual observation, and then by ascending from these to strive to reach the causes of things.” Leonardo da Vinci had advanced science and engineering in many directions; and Palissy had collected and studied a large variety of natural things. Gilbert had made his memorable experimental researches on magnetism, while Galileo had confounded orthodox philosophy by his investigations in mechanics and observations of celestial objects. Bacon drew up the rules by which he considered Nature should be studied, but he treated almost with contempt all progress accomplished without the use of his prescription, and he persistently rejected the Copernican theory, though it formed the best possible example of the application of his own system of collecting observations and arriving at conclusions from them. Few natural philosophers who came after him took heed of his artificial process of discovery ; and there is little evidence that the method assisted in the advance of science in any way. Newton never mentioned Bacon or his system, though he was born and educated after its publication; and a study of the progress of science fails to furnish sufficient reason for believing that Bacon's Novum Organum has been either a powerful source of inspiration or has provided the formula by which natural knowledge has been increased.

It is, indeed, a mistake to suppose that all scientific investigation must proceed from the general to the particular according to a prescribed formula, or be determined by any like hard-and-fast principle. Devotion to such doctrines has often led men astray and is always an undesirable obsession.

The maxim which should guide us in our work is not from the simple to the complex, nor yet, as some philosophers have taught, jrom the more needful to the less needful, but from the known to the unknown, from truths either discovered by steady effort or stumbled on by accident to new truths springing out of past acquisitions, and verified by observation or experiment. Biologists, like other scientific discoverers, have a rugged peak to climb, and are often urged to try this or that infallible method of Bacon, Descartes, or Comte, a method which generally turns out to be either misleading or impracticable. There is but one way—to wriggle up as you can, sometimes taking to the right, sometimes to the left, sometimes turning back, because what looked like a promising opening proves to lead nowhere. It is a great thing to possess natural aptitude for the work, a great thing too to be obstinately bent on getting to the top, but the successful climber often owes much to good-luck wisely turned to account. Prof. L. C. Miall.

In his New Atlantis, Francis Bacon planned in somewhat fanciful language a palace of invention, a great temple of science, where the pursuit of knowledge in all its branches was to be organised on principles of the highest efficiency. He argued that for a nation to apply a substantial part of its material resources to the equipment of scientific work and exploration, a share of its resources which should grow greater with the growth of population and the increasing complexity of knowledge, was the surest guarantee of national glory and prosperity. We still await in the United Kingdom the realisation of this institution. The Royal Society of London, which was founded for the furtherance of the experimental philosophy which Bacon wished to see pursued, had no endowment from King or country, and even now the subvention which it receives annually from the State for its own requirements amounts to only a thousand pounds towards the cost of scientific publications, together with the use of its rooms at Burlington House.

The experimental method of research represented the spirit in which the Royal Society was founded and became an organised association with a Royal Charter in 1662. No subject was considered too trivial for study by observation and experiment; and advantage was taken of every opportunity of advancing knowledge. Among the subjects brought forward at one of the earliest meetings of the Society were:

Experiments with wires of severall matters of ye same size, silver, copper, iron, &c., to see what weight will breake them. Experiment concerning the force that presseth the aire into lesse dimensions; and it was found that twelve ounces did contract 1/24 part of Aire. Experiment to show how much aire a man's lungs may hold, by sucking up water into a separating glasse after the lungs have been well emptied of Aire. Experiment of Animal engrafting, and in particular of making a Cock spur grow on a Cock's head. Whether there bee any such thing as sexes in trees and other plants; some instances were brought of Palme trees, plum trees, hollies, Ash trees, Quinces, pionies, &c., wherein a difference was said to be found, either in there bearing of fruit or in their hardness and softness, or in medical operations.

At that time and later some of the foremost men of letters exercised their powers of wit and ridicule and sarcasm upon the men who were devoting their time to the patient investigation of Nature. None of the common people, and few of the writers and scholars, could understand why valuable time should be given up to the study of “beasts, fishes, birds, snails,

caterpillars, flies,” and as to making experiments on the weight of air, even Charles II., who took great interest in the Society, is said by Pepys to have “mightily laughed at Gresham College, for spending time only in the weighing of ayre, and doing nothing else since they sat.” From the time of Galen (130-200 A.D.), the first physiologist and the last of the Greek physicians, to that of William Harvey (1578–1657), knowledge of the human body made practically no progress. Dialectic and dogma, mysticism and tradition, dominated the science of medicine, and physicians lived fifteen centuries on the capital accumulated for them by one who went to Nature for his facts. By the dissection of animals, Galen proved that the brain is the centre of sensation and receives its messages through the nerves. His authority and that of Aristotle were considered sufficient for all time upon every question relating to the human organism ; and the results of the experimental work of Harvey in the seventeenth century were opposed by dogma derived from the work of an investigator on the other side of the bridge which spanned the intervening gulf of fifteen centuries of bankruptcy of medical science. Harvey takes a place with Gilbert and Galileo as an experimental philosopher and an apostle of the scientific method. He observed things for himself, experimented in order to see Nature at work, and did not let the views of Galen or Aristotle influence his conclusions. “I sought to discover,” he says, “the motions and uses of the heart from actual inspection and not from the writings of others; at length, and by using greater and daily diligence and investigation, making frequent inspection of many and various animals, and collating numerous observations, I thought I had attained to the truth.” For nine successive years Harvey expounded his views on the circulation of the blood, and demonstrated the anatomical and experimental evidence on which his conclusions were based, in his lectures at the Royal College of Physicians. Only after this probationary period, did he give his discoveries to the world in a little book of 76 pages, published in 1628, on the Movements of the Heart and of the Blood. In this treatise Harvey established absolutely the fact of the circulation of the blood, and the fact that muscular action of the heart causes this movement. But he was unable, from his want of a microscope, to indicate the precise path along which the blood travels from the terminal arteries to the commencing veins. The large artery from the heart gives off branches to various parts of the body, and these branch off again into small arteries in different organs. Similarly, small veins carrying blood back to the heart unite to form large veins. How the blood passed from the small arteries to the small veins could only be conjectured by Harvey, and was not discovered until three years after his death. He concluded that the blood passes from the arteries to the veins mainly by percolation, as water, to use his own illustration, percolates the earth and produces springs and rivulets. No microscope in his time was powerful enough to enable him to see the meshwork of very minute tubes—the capillaries—which can now be observed easily. Improvements in the microscope enabled Malpighi in 1660 and Leeuwenhoek in 1688 to demonstrate the completion of the circuit of the blood by microscopic observations of the movement from arteries to veins

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