Measurement in Cadsoft Eagle

Hello everyone,
While I was designing an Arduino shield for my project, I realized that I couldn't measure the dimensions. I have seen the trick using the grid option and then placing the cursor different places, and that hasn't worked out for me. I have seen grid runner, and I don't think that will work out either. I think I have seen somewhere that there is a measuring tool where you draw a line and measure? If there is an Arduino R3 shield outline, where is it?

Thanks,
Qtechknow

Try to find the dimension button 8) Near the bottom of the main toolbar on the left (well in my Eagle 6 setup).

Works great. One more thing, what measurement does it use?

Qtechknow:
Works great. One more thing, what measurement does it use?

Whatever your grid is set to use.