Sorry people I have finally woken up and realised it is my fault the
chart is not working!

In fact I don't even know if what I want to do is possible.

I want to plot times against time of day which is fine for one series
like below

Time of Day Time
15:00 01:32.123
15:01 03:24:345
15:04 02:21.222

etc etc

However i want to add another series to my chart like the one above.
But the time of day is nearly the same (ie will run between the same
times such as 15:00 to 16:00) but the time of day will never be exactly
the same on the first.

I am wondering if it is possible to plot these 2 things onto one chart
accurately?