This study was drawn using graphite pencil, a material Gainsborough especially liked to use. He cared passionately about the quality of his materials, but soft graphite required fixing to prevent smudging. The denser brown around the cow suggests that a fixative was used to 'set' the graphite, which has now discoloured. One method Gainsborough described was to 'dip it all over in skim'd milk'. An initial dip in boiling water was also recommended to remove loose graphite particles. It is not known whether the fixative used here was milk, but it has the distinctive matt and age-darkened quality of milk-based fixatives.