er the present invention.FIGS. 7A and 7B are a side view and a top view, respectively, of a passive heave damper constructed according to another embodiment of the present invention on one column of the platform of FIG. 1.FIGS. 8A and 8B are a side view and a top view, respectively of a sixth embodiment of the heave damper of the present invention.FIGS. 9A and 9B are a side view and a top view, re