Results obtained for the bar widths in the four Herschel fields. Top four panels: histograms of bar width in the four individual Herschel fields. Bottom panel: combined histograms of the four Herschel fields together. In each panel, the solid line gives the normalized number of pixels whose most significant bar width is as a function of , whereas the dashed line gives the normalized number of pixels belonging to a reconstructed filament of bar width W_b as a function of W_b.