First:  uncompress the 'dos310b.lzh' file with 'LHA'.

The file 'dos310b.td0' is an image of the MS-DOS 3.10b bootable floppy
for the DEC Rainbow. It was compressed with Teledisk 2.12.

To get a bootable floppy, do the following;

 * Uncompress 'teledisk.lzh' with lha on a PC with 1.2Mb floppy drive.

 * Copy the 'dos310b.td0' to the same machine.

 * Start 'teledisk.exe' (maybe you first have to configure your system
   with 'tdconfig.exe'). Put an empty 5.25" floppy in your 1.2Mb drive
   and specify that you want to use this drive, when the teledisk program
   asks what drive you want to use.

 * Use the 'copy file to disk' option and set 'dos310b' as input file.

 * The program will now make a bootable MS-DOS 3.10b floppy for you...

The 'Teledisk' and 'LHA' programs can be found on /pub/ibmpc/util.