Common sense (and indeed scientific consensus until the mid-1700s) would seem to suggest that material "disappears" when burned, as only the ash is left. Further scientific research has found that conservation of mass holds for chemical reactions. Antoine Lavoisier, one of the pioneers in these early insights, stated: "Nothing is lost, nothing is created, everything is transformed." The burning of a solid material may appear to lose weight if the mass of combustion gases (such as carbon dioxide and water vapor) are not taken into account. The original mass of flammable material and the mass of the oxygen consumed (typically from the surrounding air) equals the mass of the flame products (ash, water, carbon dioxide, and other gases). Lavoisier used the experimental fact that some metals gained mass when they burned to support his ideas (because those chemical reactions capture oxygen atoms into solid compounds rather than gaseous water).