In the Golden Age, Plato and Aristotle walked in the Academy and in the Lyceum, instructing and disputing. We, in our time, are in possession of much of their labours ; we have entered into them, and they have become part of our inheritance. Other searchers after truth there were too in those days—artists and craftsmen—who fashioned things for delight as well as for use. But alas ! less, much less, of their works have survived to the present day. In the case of paintings (originally a great number) next to nothing now remains,. In due time, men of genius in applied science appeared, men who understood how to harness natural law to immediate needs. They had to combat the Platonic tendency to discourage investigations concerned with gross matter, and for centuries there had been the lag between discovery and application. But it may be that man was not then ready for such advances. Enough to recollect that when a giant appeared-in the person of Leonardo da Vinci-he combined consummate artist, engineer, technician and natural philosopher all in one. Perhaps sensing his own incapacity to generalize, he strove against heavy odds to study afresh the works of Archimedes, and thus, with not inconsiderable success, to effect a junction between studio and laboratory.