292 FERGUSON'S LECTURES. 



LECH thereon meet exactly, and continue all the way even 



III Kr \\ 



^-\ -x/" and whole ; the circles not breaking into several arches, 

 nor the papers either coming short, or lapping over one 

 another. 



2. See that the colours be transparent, and not laid 

 too thick upon the globe to hide the names of places. 



3. See that the globe hang evenly between the brazen 

 meridian and the wooden horizon ; not inclining either 

 to one side or to the other. 



4. See that the globe be as close to the horizon and 

 meridian as it conveniently may ; otherwise, you will 

 be too much puzzled to find against what part of the 

 globe any degree of the meridian or horizon is. 



5. See that the equinoctial line be even with the ho- 

 rizon all around, when the north or south pole is ele- 

 vated 90 degrees above the horizon. 



6. See that the equinoctial line cuts the horizon in the 

 east and west points, in all elevations of the pole from 

 to 90 degrees. 



7. See that the degree of the brazen meridian marked 

 with 0, be exactly over the equinoctial line of the globe. 



8. See that there be exactly half of the brazen me- 

 ridian above the horizon ; which you may know, if you 

 bring any of the decimal divisions on the meridian to 

 the north point of the horizon, and find their comple- 

 ment to 90 in the south poi'it. 



9. See that when the quadrant of altitude is placed 

 as far from the equator 0.1 the brazen meridian, as the 

 pole is elevated above the horizon, the beginning of the 

 degrees of the quadrant reaches just to the plane sur- 

 face of the horizon. 



10. See that whilst the index by the hour circle (by 

 the motion of the globe) passes from one hour to ano- 

 ther, 15 degrees of the equator pass under the graduated 

 edge of the brazen meridian. 



11. See that the wooden horizon be made substantial 

 and strong : it being generally observed, that in most 



