Arrange the steps of Talbot's negative-positive process in the order they are carried out.

1. Expose sensitised paper in the camera to make a paper negative
2. Develop and fix that negative
3. Wax or oil the paper to make it more translucent
4. Lay it in contact with a second sheet of sensitised paper
5. Expose the sandwich to daylight and fix the positive print

The waxing step is the one that shows the process fighting its own material. A paper negative scatters light in its fibres and prints soft, so it was oiled or waxed to reduce the scattering, a workaround that Le Gray formalised in 1851 and that glass, being transparent to begin with, made unnecessary.