You might recall that I had a dyebath left over after dyeing a cushion cover red using ground madder root.
I threw some bits of cotton, linen and wool into it, some mordanted in alum, some not. It is important to note that none of the samples were left to develop the mordant for 3 or 4 days, as was done with the original wool. The results were as below:
Wool and linen dyed in old dyebath

The mordanted linen gave a nearly nice pinkish colour, on the left. I had repeatedly heard that linen was hard to dye even with a mordant, and this was confirmed. As you can see there is some wool that is less well coloured, and that didn’t have any mordant on it at all. The piece at the top left of the group of four had no mordant, producing what was quite a nice orange. The two bottom pieces have a somewhat reddish/ brownish orange tinge to them. It also seemed from the results that the cushion cover had indeed absorbed most of the red dyestuff from the bath, despite the dark red colour of the remaining liquid.

The next part of the experiment was to heat the dyebath up to 80-85C for an hour or so, then put the sample into it for an hour at that temperature. According to what I had read, more brown colouring was released from the dyestuff above 70C or so, and so an hour or more above it should give a more brown result. This is the piece at the top right of the foursome, shown here close up with the mordanted early piece:
two pieces of wool one boiled dyed

It is a darker, browner colour, although that is hard to see on a digital photo.

Hypothesis somewhat confirmed. Mind you it wasn’t that brown. I wonder what I’m missing? Longer soak time of the dye? The effects of the previous dyeing taking out some of the dyestuff? Maybe if I fiddled around with the pH?

Either way I’ve experienced myself what those who do dyeing know already – that you can get a range of colours from madder without too much difficulty and using only authentic techniques