REPORTS FROM THE SECTIONS. 251 
To set the dec. vernier right, point the telescope to the pole, 
then turn the polar axis and adjust the telescope until it turns as a 
continuation of the polar axis, which may be known very nearly, 
by the tube turning from six hours before meridian to six hours 
after in its own diameter. To do this, put the telescope as 
directed, and the equatorial axis in the plane of the meridian, 
then bring an object to touch the side of the open end of the tube ; 
turn the axis 180°; the other side of the tube should touch the 
same object ; if not, move it until, on repeating the test, it will, 
then the telescope points to its own pole, and the vernier should 
d 90°. 
Now, when this is adjusted, and the telescope tried on a star, 
and the observed declination does not agree with the tabular posi- 
and south, the greater the declination the better. If clock error 
by each of these is the same, instrument is in meridian ; if not, 
star (well known) and about six hours from meridian correct for 
= is on declination wire, instrument is on 
meridian, if not adjust. 
en in meridian, adjust hour circle vernier to read Oh. when 
a star is on meridian : 
Maker must set the declination axis at right angles to the polar 
axis, 
ere W: 
in construction, it would be impossible to get both ends of the tube to turn 
180° in a diameter. 
