LABORATORY ( from the mediaeval Latin laboratorium, a workshop). The word is used to denote any room or building devoted to experimental investigations in technics and the sciences for the purpose of advancing man's knowledge of special applications of natural law or of human physiology and mentality. Lab oratories have been introduced into educational institutions to teach scientific and technical knowledge by means of experiments. The term is used to denote the workroom of a manu facturing chemist, or to the testing-rooms of an industry. In early times the nature of the chemical work of making drugs and potions was more or less disguised by the priesthood who called the place where they were made simply a workshop. Out of these early labora tories grew those of the Middle Ages. In this later period they were devoted to astrology, the making of drugs, potions and charms and to the search for the philosopher's stone by means of which it might be possible to change the baser metals into gold. Some of these laboratories were very important in that day, being patronized by the nobility or maintained at the public expense.
Among the first laboratories open to students were those of Purkinje, who established a physiological laboratory at Breslau in 1825, and the chemical laboratory of Baron von Liebig at the University of Giessen in the same year. The first physical laboratories for students were founded about 1846; one at Heidelberg, by Philipp Gustav Jolly, and one at the University of Glasgow by William Thomson — Lord Kelvin.
Among the great laboratories of the world may be noted that of the Royal Institution, established in 1800 by Count Rumford, which was to be devoted to the applied sciences, but which soon became the seat of great activity in researches in pure science, conducted by such men as Davy, Faraday and Tyndall. The Physikalische Reichsanstalt, in Charlottenburg, near Berlin, was a very famous laboratory where there were departments devoted to re search in pure science, and other departments for the study of the application of science to industrial pursuits. In 1875 a committee of
weights and measures, made up of represen tatives of 18 nations, was organized for the purpose of reproducing and furnishing inter , _ national metric standards to the members. A laboratory for their manufacture and for re search was established near Paris. Great Britain has placed with the Royal Society the control of its National Physical Laboratory, where standards of weights and measures are to be kept, duplicates made, instruments tested and research is to be carried on. In the United States the Smithsonian Institution (q.v.) was established in 1846_. Many important lines of research have been developed there, out of some of which have grown up some govern mental departments, as the United States Weather Bureau and the United States Fish Commission. The United States government has established, by act of Congress, approved 3 March 1901, a National Bureau of Standards, a suitable building and equipment also being provided. The buildings and equipment have been added to until there are over half a dozen well-appointed buildings in use. The bureau has the custody of the standards of weights and measures, and has power to manufacture duplicates, multiples and submultiples. It also has the power officially to test and calibrate physical and chemical apparatus and issue cer tificates for them. A great deal of work is done in standardizing and calibrating physical, chemical and technical apparatus and machines for educational institutions, manufacturing plants and various governmental departments. Tests of commercial products are carried out and standard specifications adopted, unifying and in many cases simplifying them. Re searches in pure and applied sciences carried on have been of the greatest importance in technical and commercial work. Especially have important results been attained during the World War, in solving such problems as the production of optical glass, increasing the pro duction of fuel for internal combustion en gines and aid in the further development of wireless telegraphy and wireless telephony.