Scatter plots of measured parameters for the 47 VCFs. The values are averaged along the crests of the VCFs. The data points in red, yellow, and blue indicate VCFs 1, 32, and 47, respectively. Left: velocity dispersion vs. column density. The horizontal and vertical bars indicate the 1s dispersions of and s_v about their average value along the crests. The diagonal line shows the best power-law fit . Middle: velocity gradient G_v (given in absolute value) vs. column density. The horizontal bars indicate the 1s dispersion of (same as left panel). The vertical bars give the 1s uncertainty of the linear fits to the velocity fluctuations along the crests. Right: velocity dispersion vs. G_v (given in absolute value).