Hi Buzz,
In addition to salary scales (which are a public service thing) the Universities have a thing called "above the bar" and "below the bar". Im not certain but I think there are different terms and conditions accruing to the both. Try a google search with the following (NUI, "salary scale" and bar) and you should get some hits explaining it better.
€19,358 x 7 = €24,688/Bar/€24,753 x 6 = €31,314 p.a.
I assume this means 7 equal annual increments from €19,358 to €24,688
then you step above the bar to €24,753 with 6 equal annual increments to €31,314
Depending on your experience I think you can step in at any point along the scale and then continue to the top of the scale.
I hope this makes sense to you.
ajapale