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Aiming

Although the subject of aiming comes last in this discussion, it is one of the first things with which the archer must become familiar if he is to become an accomplished marksman. In target shooting, aiming is a most important part of the preparation, and it must be done with precision. Because of the large effect of gravity on the trajectory of the arrow, a system of aiming must be worked out in which the line of aim uniquely establishes initial elevation and azimuth of the arrow to assure its hitting a mark at a particular distance. The arrow is usually drawn so that the index finger is below the chin, pressing upward against the jaw, and with the aiming eye in the vertical plane containing the arrow. One method of sighting is to look over the tip of the arrow at some fixed point, called a point of aim. For short distances this is on the ground in front of the target; for long distances it is above the target. This point corresponds to that particular elevation of the arrow which produces an accurate hit at the location of the target. The greater this distance the greater is the elevation, and therefore the greater is the distance or elevation of the point of aim relative to the archer. For a given bow and arrow there are two distances at which the line of aim, as described, intersects the path of the arrow. If the more remote of the intersections occurs at the center of the target, its distance is called the point-blank range. For greater distances, the point of aim is above the mark to be hit. For shorter distances the point of aim is below this mark.

Various sights have been devised. These are designed for attaching to the bow. They permit direct aiming at the point to be hit. A bow sight may be as simple as the head of a pin projecting from behind the bow above the arrow, where the pin may be held in a strip of adhesive; or it may be as complicated as a calibrated slide with fine adjustments for the sighting point. However, a mechanical sight is ordinarily not suitable for distances approaching and exceeding the point-blank range. For such cases a sight may be used in which the target is viewed through a prism of small angle, provided with a fixation mark for aiming. Without going into details of construction, it may be said that the prism sight is perhaps the most convenient of the several types of sighting devices, but that many archers still use the point of aim, and indicate it by a marker set in the ground. The latter method obviously requires that the archer stand in a fixed position relative to the marker so that successive shots will fly alike in azimuth as well as in altitude.

One source of error in shooting, causing lateral deviation, comes from tilting the bow by varying amounts from the vertical. Skilful archers have habituated themselves to checking the tilt by sighting the string on some vertical line, like the lines on a building, to keep the bow tilt zero or at a constant, finite angle. Another source of inaccuracy, causing variations in "length," is the failure to hold at full draw before releasing—a malady called "creeping." It comes at the part of the draw where small differences cause large changes in initial velocity. No refinement in sighting means can correct for such faults—and others—in the archer's method.