(2) A way to obtain true latitude is to take two smooth pieces of wood, about 1 foot long and ¼ inch thick, and hinge them together at one end with a screw, as in Fig. 96. Now set a bucket out-of-doors in an open space from which the North Star may be seen, fill the bucket with water and level it up until the water is parallel with the rim all the way round. When night falls find the North Star and set your sticks across the rim, as shown in Fig. 97. Raise one of the sticks and sight it until it points straight at the North Star, and having done this you are through with the observation. Take the sticks into the house, being very careful not to change their relative positions, so that the _angle_ they form can be measured with a protractor. Tack a piece of paper on your starboard and draw a straight horizontal line on it. Lay the stick that was on the bucket on the horizontal line, and draw a line along the edge of the other stick with which you sighted the North Star, as in Fig. 98. Now measure the distance, in degrees, between the two lines with your protractor and the number of degrees you get will be roughly the latitude. =Shooting the Sun.=—Another and very exact way to find the latitude, and which is also used to help find longitude when at sea, is by means of an instrument known as a _sextant_, so called from the fact that it is formed of a sixth part of a circle. [Illustration: FIG. 98.—PROTRACTOR AND STICKS ON DRAWING PAPER.] It is made with a metal frame A and having the degrees marked on its curved edge B like a protractor. On one end of a thin strip of metal, or arm, C (see Fig. 99), a mirror, D, called an _index mirror_, is rigidly fastened, and right under the center of this mirror the arm C is hinged to the frame A. The other end of this arm slides over the scale B. To the left side of the frame also rigidly fastened is a second glass E called a _horizon glass_, and half of which is clear and half silvered. A _telescope_ is also rigidly fastened to the frame A directly opposite but in a line with the horizon glass E. Now to find the latitude by _taking the Sun_, or as sailors sometimes call it, _shooting the Sun_, in order to learn the position of the ship at sea, the sextant is held in both hands firmly, and the horizon which is sighted through the telescope is brought into view through the clear part of the horizon glass E.