In addition to the researches that have been made on the mechanical properties of the bow and arrow, and the conditions that affect their performance, a number of papers have been published on studies of aiming, holding, sights and points of aim. Advantages of the sight over the point-of-aim marker have been enumerated. In a comparison between the two, it becomes evident that, so far as the technique of shooting is concerned, there is no difference whatever between them. A sighting device in effect produces a fixed point-of-aim; it is precisely like putting a massless extension upward on the pile of the arrow, and sighting over that at a point of aim. The length of this imaginary upward extension is determined by the distance of the target. In addition, the sighting point makes possible lateral adjustments for wind. It also gives the archer some freedom as to position on the shooting line. If the sight— which may be simply a bead—is artificial, so is the point-of-aim marker. The principal difference between them is that the sight has the great advantage of convenience; when changing distance, shifting the sighting point is far less bothersome than moving the point-of-aim marker. On the other hand, since the technique of shooting involves so many psychological factors that are not well understood but which have a profound effect on scores, the individual archer should investigate whether in his own case the sight or the marker gives better results.
This review is not controversial; on the contrary, it is intended to be an uncolored presentation of the conclusions reached in various investigations. As to the "propriety" of using the sight or the marker, no conclusions based on facts can be reached, since this is altogether a matter of opinion. It is interesting in this connection to note that in certain archery events in England, such as the Scorton arrow shoot, the use of a bead on the limb of the bow is permitted, but not the marker. If "artificialities" are to be banned, both should be excluded; but no rules can be made against the archer's selecting some "natural" marker on the ground. Perhaps the best test of an archer's ability to gage the proper elevation for a particular distance would be to have such uniformity of terrain between shooting line and target that no natural marker could be found. He would then be compelled to estimate the location of his point-of-aim for each shot, or to shoot instinctively. 
Using the data obtained in the study of the flight of an arrow, with allowance for air resistance, as a basis, Klopsteg computed tables and curves that give the relation between the target distance and (a) the distance of the point-of-aim marker on the ground, measured from the target, and (b) the distance of a sighting point or bead above the axis of the arrow, for arrow velocities ranging from 130 to 180 feet per second. Computations were made for 325-grain and 400-grain arrows. From the tables it is possible, knowing arrow weight, to obtain approximate arrow velocities when the locations of points of aim for different target distances (or sight settings), are known. When the arrow velocity has been found, a single determination of the location of the point of aim, or sight setting, for a known distance, enables one to set points of aim or sights for any other distance. The curves also show that for every arrow velocity within the values mentioned, there are two different target distances for which the distance from the target to the point-of-aim marker is the same. For example, with an arrow of 161 f.p.s., the marker is 30 yards from the target for the 80-yard range; it is precisely the same with the target at 45 yards. Likewise, with a 140 f.p.s. arrow, the marker for the 60-yard range is 20 yards from the target; it is also 20 yards from the target when the latter is 35 yards away. The same computations give point-blank distances for each arrow velocity. These distances are: 130 f.p.s., 63 yards; 140 f.p.s., 72 yards; 150 f.p.s., 82 yards; 160 f.p.s., 92 yards; 170 f.p.s., 103 yards; 180 f.p.s., 114 yards. Depending on the archer's stature, his anchor, and the length of draw, there will be slight variations in these values. Such a tabulation enables one to determine his arrow velocity by finding the point blank range for his bow and arrow; and from it, the marker or sight settings for all the ranges.