Frost’s painting in the early 50’s sits at the very centre of the debate between the experience-influence abstracted images of the St Ives painters and the theoretical, rigorously constructivist work of his Camberwell contemporary Victor Pasmore and friend, former Slade pupil, Adrian Heath. Frost’s work from this period has a crucial place in British abstract art of the immediate post-war period. Frost sought to find a visual language which would express in an abstract idiom the sense of place and movement found in the harbour of St Ives. In the group of works to which Blue Harbour belongs, sophisticated geometrical relationships are used to suggest familiar forms and shapes whilst never actually offering us identifiable references. These paintings also see the earliest appearances of what was to become the standard vocabulary of Frost’s art: the semi-circles, the highlighted discs and the truncated L and T forms. The paintings from this time are also distinctive in their use of colour, each having one overall dominant palette. In Blue Harbour the masterly use of bright ultramarine and other shades of blue suggests boats at anchor and the incoming tide to create an image of great power and impact.