(a) Sample spectrum from the southern edge of the C feature at position ﹩\alpha =13^{\mathrm{h}\,}27^{\mathrm{m}\,}47\fs 608﹩, ﹩\delta =47^{\circ }26^{\prime }50\farcs 25﹩. (b) Sample spectrum from the northern edge of the C feature at position ﹩\alpha =13^{\mathrm{h}\,}27^{\mathrm{m}\,}47\fs 806﹩, ﹩\delta =47^{\circ }27^{\prime }04\farcs 25﹩.