The emptiness of Martin Johnson Heade's landscape paintings gives them a modern look. This is easy to see if you compare them with, say, Jacob van Ruisdael's broadest landscape views of two centuries earlier. Ruisdael's space stretches far from the eye, but it looks populated: it is the space of the human world whose dignity seems to be attested by the vastness of sky above. As encompassing as his views may be, the world is Van Ruisdael's subject, whereas Heade's is the earth, terrestrial space itself, and the light that unifies it. Human figures have a compositional place in Heade's pictures, but not a thematic one. In ''Approaching Storm Near Newport,'' only the boats under sail betoken the human presence, and they are little more than markers used to articulate the picture's tremendous illusion of depth. Whenever I see one of Heade's landscapes , and this one in particular, I remember the opening lines of Charles Olson's essay on Melville: ''I take SPACE to be the central fact to man born in America, from Folsom cave to now. I spell it large because it comes large here. Large, and without mercy.''
Many of Heade's landscapes are less ominous in mood than ''Approaching Storm. . . .'' But in nearly every case, the prevailing mood of a picture seems to be set by the character of the space and the way it is filled with light. Art historians have coined the term ''Luminism,'' to denote the lucid handling of light and shadow found in landscapes by Heade and a few of his contemporaries, such as John Kensett, Fitz Hugh Lane, and Sanford Gifford. It is a striking fact that the Luminists developed their focus on light and space at roughly the same time as the Impressionists in France were making light effects the basis of innovations in painting style. Despite their similar preoccupations, the American and French painters took their respective works in stylistically opposite directions. The Luminists deepened and clarified spatial illusion, while the Impressionists placed increasing emphasis on the picture surface by using paint to evoke, rather than depict, visual experience.
Heade and the other Luminists rendered space as if it were one of the world's absolutes. Even though his landscapes appear to move in the direction opposite to that of European Modernist painting, they may still be seen as presaging certain works of twentieth-century American abstract painting. Nineteenth-century American paintings are as empty as Heade's. The more we look for anecdotal themes in them, the more we are led to the conclusion that Heade's real subject is space, and that the landscape elements he uses are those he thought necessary to make such an abstract theme possible. The longer we look at ''Approaching Storm . . . ,'' the less surprising it becomes that the picture brings to mind abstract works of a century later by such artists as Mark Rothko and Kenneth Noland. Rothko especially tried to revive by means of color alone the associations between pure space and the divine presence in nature that might have been quite immediate to Heade and his contemporaries.