eSignal high low over time period

Is there an easy way to draw lines that show what the high and low are over the last 1 hour of trading?

Yes, just use Donchian Channels. They are on the Basic Studies menu when you right click on an advanced chart.

If you have a 5 minute chart then set the Length to 12 (60 min / 5 min = 12 bars per hour) and a Length of 60 will work on a 1 minute chart etc.

The Donchian Study shows you the high/low (and midpoint line if you want) over the last X number of bars so will also work on Volume and Tick charts although you would obviously not be able to set it at a time interval then - you could only use number of bars then.

Let me know if this is what you are looking for...