Explanation of the DEVICEHIGH command. It is CONFIG.SYS.

This command will help you load your devices into extended 
or expanded memory.

Example:
       To load your ANSI.SYS device, which is located in drive A,
       into the extended/expanded memory of your computer,
       you would have to include the following line in your
       CONFIG.SYS file:
            devicehigh=a:ansi.sys