
Figure 1
‘Mistress and maid’, by Johannes Vermeer (public domain), c. 1666–1667, The Frick Collection, NYC, USA. (Source https://upload.wikimedia.org/wikipedia/commons/6/61/Vermeer_Lady_Maidservant_Holding_Letter.jpg).

Figure 2
‘Lady seated at a virginal’, by Johannes Vermeer (public domain), c. 1670–1672, The National Gallery, London, UK. (Source https://upload.wikimedia.org/wikipedia/commons/5/55/Lady_Seated_at_a_Virginal%2C_Vermeer%2C_The_National_Gallery%2C_London.jpg).
