In the about 200 volumes of the 6th Edition and the NewSeries of the Landolt-B|rnstein Handbook a lot of valuablephysical and chemical information is collected by experts.The Landolt-B|rnstein Substance Index 1993 was designed tohelp the user to find out in an easy way whether data forspecific substances and physical properties of interest arepresent and secondly, in which volumes he has to look.Each subvolume of the Substance Index is accompanied by afloppy disk for MS-DOS and compatibles allowing annualupgrades (compressed Word 5.0 textfiles for MS-DOS andcompatibles). Together with the Landolt-B|rnstein DirectoryDisk 1.0- a Comprehensive Index as a PC-Database whichallows search for physical properties - much easier accessto the handbook collection than before has been achieved.