text: Several factors led to the first chemical revolution.  First, there were the forms of gravimetric analysis that emerged from alchemy and new kinds of instruments that were developed in medical and industrial contexts.  In these settings, chemists increasingly challenged  hypotheses that had already been presented by the ancient Greeks. For example, chemists began to assert that all structures were composed of more than the four elements of the Greeks or the eight elements of the medieval alchemists. The Irish alchemist, Robert Boyle, laid the foundations for the Chemical Revolution, with his mechanical corpuscular philosophy, which in turn relied heavily on the alchemical corpuscular theory and experimental method dating back to pseudo-Geber.
  Earlier works by chemists such as Jan Baptist van Helmont helped to shift the belief in theory that air existed as a single element to that of one in which air existed as a composition of a mixture of distinct kinds of gasses. Van Helmont's data analysis also suggests that he had a general understanding of the law of conservation of mass in the 17th century. Furthermore, work by Jean Rey in the early 17th century with metals like tin and lead and their oxidation in the presence of air and water helped pinpoint the contribution and existence of oxygen in the oxidation process.
  Other factors included new experimental techniques and the discovery of fixed air (carbon dioxide) by Joseph Black in the middle of the 18th century. This discovery was particularly important because it empirically proved that air did not consist of only one substance and because it established gas as an important experimental substance. Nearer the end of the 18th century, the experiments by Henry Cavendish and Joseph Priestley further proved that air is not an element and is instead composed of several different gases. Lavoisier also translated the names of chemical substance into a new nomenclatural language more appealing to scientists of the nineteenth century. Such changes took place in an atmosphere in which the industrial revolution increased public interest in learning and practicing chemistry. When describing the task of reinventing chemical nomenclature, Lavoisier attempted to harness the new centrality of chemistry by making the rather hyperbolic claim that: