This next one is called "puff gathering" and I show back and front of the sample.
The gathers are small circles set out at regular intervals.When gathered the fabric pulls into regular folds.
This is called "furrowing".The top fabric is gathered along each edge and pulled up to fit a shape below,in this case another square which is 1/4 of its size.The fabric is then caught down into "furrows" to make it fit.
This bottom example is opposite edge gathering which allows the fabric in-between to form soft folds.
on the straight grain,on the bias and at right angles.
The bottom sample is two straight stitch channels with a straw gathered onto them.