The introduction and increasingly widespread adoption of the experimental method during what was known as the "scientific revolution" gave a powerful stimulus to the construction of instruments and machines for the purpose of demonstration through experiment. Major collections of such devices were soon assembled. Carrying on the radical reform program initiated by Galileo Galilei, René Descartes, and other scientists, Isaac Newton laid the foundations of classical mechanics in his Principia Mathematica. Beginning in the late sixteenth century, this theoretical redefinition of the principles of mechanics was aided by the invention and construction of apparatuses for the experimental study of the laws of motion, as well as models to demonstrate the working principles of simple and compound machines. From the early eighteenth century, the growing vogue for lectures in natural philosophy accompanied by experimental demonstrations contributed to the dissemination of a wide range of efficient devices ingeniously designed to illustrate the basic concepts and phenomena of Newtonian mechanics. Many of these devices remained in use for more than two centuries in physics collections.