Abstract: A reticle for use in a firearm scope that compensates for the trajectory of a bullet, allowing the shooter to accurately engage the target despite the target's distance from the shooter. The reticle uses a number of trajectory arcs and distance markings that correspond to the target's size and distance to provide the shooter with an accurate aiming of the target. Once the outer edges of the target aligns with the trajectory arcs the target is ready to be engaged. Distance markings, windage markings, and reticle illumination provide for further accuracy of the shot. A milling tree integral to the reticle provides for a quick determination of the target's distance, particularly in instances when the target is not intended to be engaged.

Abstract: A rangefinder system includes a bow that may launch an arrow. A range finder is provided and the range finder may determine a distance between the bow and a target. A mount is coupled to the bow such that the mount is directed forwardly from the bow. The range finger is coupled to the mount such that the mount directs the range finder forwardly with respect to the bow. A switch is coupled to the bow and the switch may be manipulated. The switch is electrically coupled to the range finder such that the switch turns the range finder on and off. A display is movably coupled to the bow and the display may be visible. The display is electrically coupled to the range finder and the display displays a distance between the range finder and the target.

Abstract: A survival device for use in an emergency situation includes a battery, a lamp, and a detection circuit for detecting an occurrence of the emergency situation and for switching the lamp to be powered by the battery when such an occurrence is detected. In one form, the detection circuit detects a presence of water along a surface of the device, with safety tools for escaping from an submerged vehicle being provided. In another form, the detection circuit detects a failure of electrical service within a building, with safety tools for escaping a fire being provided.

Abstract: There is disclosed a framing T-Square and protractor wherein the head of the T-Square and the elongated rule thereof are connected by means of a ballbearing allowing the rule portion to be free-swinging with respect to the head, which is in the form of a rectangular plate having a protractor scale thereon marked in degrees and auxiliary scales marked with inches of rise per 12 inches of run for common rafters and for hip and valley rafters. A rectangular panel is hingedly attached to the plate on a hinged line normally at right angles to the elongated rule; a friction locking mechanism permits the rule to be locked at any desired angle relative to the plate and panel. The rule, plate, and panel are marked on the back with rafter tables and other data including run lengths and protractor angle settings useful in roof framing and other construction or carpentry work. A vernier scale on the front of the panel facilitates setting of angle measurements to an accuracy of one-tenth of a degree.

Abstract: A pendulum level which is a combination pendulum and level. It includes a rectangular frame with no back and front panels and two spaced cross bars, a pendulum that is pivotally secured to one of the cross bars and detachably secured to the other cross bar, and a level which is adjustably secured to the side of the frame. The location of the pivot point of the pendulum and the use of a longer and heavier pendulum allows the pendulum to swing freely yet quickly settle to the truly vertical. The pendulum type operation depends only on gravity for accuracy and will not get out adjustment as presently made levels do. A long vial is used in the level because it is more accurate, easier to see and use. The mounting system of the vial allows for the adjustment of the vial when it is not true. The vial is exposed for easy cleaning.

Abstract: A grade liner which is used in cooperation with grade stakes to determine the grade within a ditch. Means are provided for establishing a horizontal line of sight a selected rise distance "A" above a grade stake. Plumb means are provided which intersect the established horizontal sight line a given offset distance from said stake. The plumb means is calibrated such that the zero calibration is located a selected distance related to said rise distance "A" from the lower end of said plumb means. In a preferred embodiment of the invention, optical means, such as a target sighting rifle scope, are utilized in establishing a desired horizontal sight line. For the plumb means, a surveyor's tape measure may be utilized when coupled to a plumb bob, the length of which bob is selectively determinable and related to the distance said sight line lies above the grade stake.

Abstract: A transparent plumb bob having a fixed point and an associated movable point, to be aligned therewith for determination of a vertical line through a given exterior point, optionally including means for horizontal leveling and easily securing the bob intermediate the ends of a string. A vertical or horizontal line is determined by fixing one string end to a point spaced from the plumb bob and then pivoting the plumb bob and other string end about the point until the associated indicators are in alignment.

Abstract: A motion detection device is characterized by an array of mutually spaced electrical contacts connected to one terminal of a pair of terminals having a voltage differential established therebetween, an electrically conductive first mass suspended between the pairs of contacts and connected to the other terminal of said pair, and a mass suspended from said first mass for damping pendulous motion of said first mass.