The INSTR function should help here.
If you know that it will allways be 4 parts in stn, you could use a query like this:
<pre>select substr(stn,1,instr(stn,' ',1,1)-1) n1,
substr(stn,instr(stn,' ',1,1)+1,instr(stn,' ',1,2)-1-instr(stn,' ',1,1)) n2,
substr(stn,instr(stn,' ',1,2)+1,instr(stn,' ',1,3)-1-instr(stn,' ',1,2)) n3,
substr(stn,instr(stn,' ',1,3)+1,length(stn)) n4
from YourTable;</pre>
If not, you could create a stored function or procedure with a similar logic.
Please reply if you need more help.