SCIENTIFIC METHOD--GILBERT, GALILEO, HARVEY, DESCARTES The previous chapter has given some indication of the range of the material which was demanding scientific investigation at the end of the sixteenth and the beginning of the seventeenth century. The same period witnessed a conscious development of the method, or methods, of investigation. As we have seen, Bacon wrote in 1620 a considerable work, _The New Logic_ (_Novum Organum_), so called to distinguish it from the traditional deductive logic. It aimed to furnish the organ or instrument, to indicate the correct mental procedure, to be employed in the discovery of natural law. Some seventeen years later, the illustrious Frenchman René Descartes (1596-1650) published his _Discourse on the Method of rightly conducting the Reason and seeking Truth in the Sciences_. Both of these philosophers illustrated by their own investigations the efficiency of the methods which they advocated. [Illustration: _Painting by A. Ackland Hunt_ DR. GILBERT SHOWING HIS ELECTRICAL EXPERIMENTS TO QUEEN ELIZABETH AND HER COURT] Before 1620, however, the experimental method had already yielded brilliant results in the hands of other scientists. We pass over Leonardo da Vinci and many others in Italy and elsewhere, whose names should be mentioned if we were tracing this method to its origin. By 1600 William Gilbert (1540-1603), physician to Queen Elizabeth, before whom, as a picture in his birthplace illustrates, he was called to demonstrate his discoveries, had published his work on the Magnet, the outcome of about eighteen years of critical research. He may be considered the founder of electrical science. Galileo, who discovered the fundamental principles of dynamics and thus laid the basis of modern physical science, although he did not publish his most important work till 1638, had even before the close of the sixteenth century prepared the way for the announcement of his principles by years of strict experiment. By the year 1616, William Harvey (1578-1657), physician at the court of James I, and, later, of Charles I, had, as the first modern experimental physiologist, gained important results through his study of the circulation of the blood. It is not without significance that both Gilbert and Harvey had spent years in Italy, where, as we have implied, the experimental method of scientific research was early developed. Harvey was at Padua (1598-1602) within the time of Galileo's popular professoriate, and may well have been inspired by the physicist to explain on dynamical principles the flow of blood through arteries and veins. This conjecture is the more probable, since Galileo, like Harvey and Gilbert, had been trained in the study of medicine. Bacon in turn had in his youth learned something of the experimental method on the Continent of Europe, and, later, was well aware of the studies of Gilbert and Galileo, as well as of Harvey, who was indeed his personal physician.