We have previously used neutron scattering to study the melting transition in fibre DNA, measuring the change in the intensity and shape of Bragg peaks as a function of temperature to determine the spatial correlations along the molecule and comparing the results to statistical mechanics models. Our work did not account for the effects of confinement, imposed by the fibre structure, on the melting transition. We now wish to study those effects by immersing fibre DNA in solutions that will allow the samples to swell, but not to dissolve. The solutions will be water containing either polyethylene glycol (PEG), thereby applying osmotic pressure to the samples, or ethanol of sufficient concentration that the DNA is immiscible.