I think your questions have got to be in the form of questions - maybe a
little more info than just "it's not working" would be helpful.



If you subtract the earlier time  from the later time, you get the elapsed
time, in a fractional portion of a day. So, for example, instead of 30
seconds, you get 3.47222222222222E-04, which is the portion of a day that 30
seconds is. If you understand that, the next question is what are you trying
to do with the result?