In the late 1950's, Johnstone redeployed spontaneous calligraphic line which first appeared in his works of the early 1930's to integrate and increase the form of design of the two dimensional structure of the irregular forms of colour, typical of his paintings of the mid 1950's.

Douglas Hall in his monograph (William Johnstone, Modern Scottish Painters University Press, Edinburgh. 1980, p.52) refers to this change in the use of line 'The curvilinear line of his pre-war compositions was replaced by a new form of drawing in sharp energetic lines, hooks and dashes. This was a profound change. The new line did not generate dillusions of organic forms in space as the old line easily did. It was a much more direct, calligraphic or 'handwritten' expression of feeling.