Confused with pattern instructions for edging of a cuff

I am working on a shawl that also has cuffs. I am now at the edging of the cuff but am stuck. Following are the instructions:
"EDGING: Row 1: Ch1, do not turn; work 48 sc evenly spaced across end of rows; working in free loops of beginning ch, (sc, ch 1, sc) in ch at base of first sc, sc in each ch across to last ch, (sc, ch 1, sc) in last ch; work 48 sc evenly spaced across end of rows; do not join."

1. What is "ch at base of first sc"? I'm having trouble seeing it since I am now working across the ends of the rows.
2. Also, when it says "ch" is it referring to the different stitches at the end of each row? Some rows were sc and other rows were hdc.

I would really, really appreciate some help on this.


ch= chain

chain stitch meaning you place your hook into that chain..

ch 1 = means chain one