Abstract: A viewing device permitting users to view true, non-reversed images of objects out of the viewer's normal line of sight as, for example, an image placed or projected behind the viewer. The device includes at least one pair of mirrors adjustably disposed in substantially direct side-by-side relationship to form a mutual angle. While the mirrors may be supported in a variety of ways, they are preferably disposed to rotate about a common axis, and may be held in place by friction mounts. In the present structure, the common axis is represented by a generally vertical support, which itself is adjustably attached to a second support so as to be adjustable and three-dimensionally rotatable. To adjust the reflective angles of an image being viewed, pressure applied to the housing of one mirror causes it to pivot against its frictional mount so as to change its angular relationship with respect to the second mirror. Either or both mirrors may be adjusted to perfect the view.

Abstract: It is known to use a rigid cone to provide stability to a body being towed by an aircraft. However, such cones are useful over a limited range of speeds. The invention provides a drag-producing aerodynamic device in which the cross-sectional area of the structure producing drag is variable. The cross-sectional area of the structure producing drag decreases as the towing speed, and hence the dynamic air pressure acting on the structure producing drag, increases and vice versa.