Top line is long pencil lead.
Unbroken pencil lead can be used as low value resistors (1 - 5000 ohms). Wooden pencils or mechanical pencil lead can be used. Wooden pencil cut off eraser and metal top. Measure resistance of total length of pencil lead and cut slightly longer than needed ohms. Bend wire around nail about same diameter as lead , crimp slightly and solder on wire being careful not to damage or break lead.
Also, for adjustable resistor, make slider connector to use with long piece of lead
Wood pencil tapped at several points with wire pigtails can may be used.
Resistance of lead depends on type, diameter, and length.
