48 Description and Use of the

8zi Any straight line passing through thecenter of a globe, being terminated by itssurface j is called a diameter; and that dia»meter about which the globe turns, is calledits axis; the extremities of which are calledthe poles of the globe.

83. There are two artificial globes. Thaton which the surface of the earth is repre-sented, is called the terrestrial globe.

84. The other on which the face of thestarry Iphere is delineated, is called the ce-lestial globe.

85. In the use of the terrestrial globe, weare to consider ourselves standing upon somepart of its surface, and that its motion re-presents the real diurnal motion of the earth,which is from west to east.

86. In the use of the celestial globe, we areto suppose ourselves at the center, and thatIts motion represents the apparent diurnalmotion of the heavens, which is from eastto west.

87. Note, The stars being delineated uponthe convex surface of the celestial globe,we must suppose ourselves at the center;because under such a supposition they would

appear,