SIGHTS. The means by which cannon or small arms are pointed or aimed. There are almost as many varieties as there are varieties of weapons. With modern high-power gulls, telescopic sights are necessary on ac count of the difficulty of seeing the target at the ex treme long range of which these guns are capable. The Scott telescopic sight, the invention of an English navy officer, with its va rious modifications, is prob ably the most generally used. In small arms two points are installed, one near each end of the bar rel, so that when the rifle or pistol is brought to the position of firing the sights come readily into coinci dence for the eye and en able the aim to be directed at the object. The sights must represent the direct line in which the bullet is projected. It is evi dent, therefore, that some form of adjustment is necessary if the sights are to be used at more than one distance. In military rifles sufficient adjustment must be given to enable the aim to be accurately taken at any range up to 2500 yards. Military sights are all variations of one general type and usually consist of a leaf either lying flat or hinged upon a bed or block fixed to the barrel. The leaf must be raised to secure ad ditional elevation, the distance being regulated by a sliding bar, in the centre of which a notch has been cut, through which the sight is taken over the tip of the foresight.
The wind gauge is a device which enables the marksman to direct his sight on the object aimed at, although the rite is actually pointing to the right or left of the mark.
As yet this device has only been used for long distance rifle-range matches and fine shoot ing. Lateral adjustment is rarely necessary at the distances at which sporting rifles are used, and it is not univer sally advocated as a feature of the small arm, owing to the difficulty t h e r e would be in securing a transverse 81 i d e which shall not be so small and so stiff as to be worthless in the excitement of action, or when the soldier's fingers are cold. Sportsmen sometimes employ a foresight of the covered bead var iety, or the ivory or copper sight used by African hunters. The Boers, who rank high as practical marks men, employ the ivory foresight, but Euro pean and American sportsmen who have engaged in African or big game shooting generally use the cop per sight. Various forms of rear sight are in use, perhaps the best of which is the platina bar on a more or less open V. Another favorite type is the platina pyramid, which is set below a very open V.
Telescopic sights are affixed to sporting rifles, and have been found very successful in deer stalking or any form of hill and mountain limit ing where game is difficult to locate. See GUN