Rachel Whiteread - Embankment 2005

Whiteread's installment, at first glance, seems to be more about positive space than negative. The jagged shapes and broken lines throughout the sculpture do not in themselves create negative space but rather demarcate the edges of the sculpture just as a simple single straight line would. The lack of color in the sculpture gives it an eeriness and reminds me of an otherworldly landscape or cityscape.
This sculpture is actually composed of individual, autonomous blocks that are casts of the insides of empty cardboard boxes. Really, then, the whole sculpture plays with the idea of negative and positive space "switching" the negative to positive.