Half-century history of clathrate chemistry

This paper is devoted to the history of a,Icl-l field of knowledge - clathr ate chemistry, whose 50th anniversary is being celebrated. The Historical D ates section contains data on clathrates from the first observations of the e compounds (late 18th century) to the pioneering works (1947-1948) of the English crystallographer Herbert Marcus Powell explaining their nature. Maj or trends of research into clathrate chemisstry since Powell's works are di scussed.