THE USE OF THE TERRESTRIAL GLOBE. 313 



pricern (as the latitude is north or south) comes to the LECT. 

 horizon ; and the index will then point out the time of ' 

 sun-setting, for it will have gone over all the afternoon 

 hours, between mid-day and sun-set ; which length of 

 time being doubled, will give the whole length of the 

 day, from sun-rising to sun-setting. For, in all lati- 

 tudes, the sun rises as long before mid-day, as he sets 

 after it 



PROBLEM XXVII. 



To fotd iti what latitude the longest day is of any given 

 length less than 24 hours. 



If the latitude be north, bring the beginning of Cancer 

 to the brazen meridian, and elevate the north pole to 

 about 66J degrees ; but if the latitude be south, bring 

 the beginning of Capricorn to the meridian, and elevate 

 the south pole to about 664 degrees : because the long- 

 est day in north latitude, is when the sun is in the first 

 point of Cancer : and in south latitude, when he is in 

 the first point of Capricorn. Then set the hour-index to 

 XII at noon, and turn the globe westward, until the 

 index points at half the number of hours given : which 

 done, keep the globe from turning on its axis, and 

 slide the meridian down iu the notches, until the afore- 

 said point of the ecliptic (riz. Cancer or Capricorn) 

 comes to the horizon ; then, the elevation of the pole 

 will be equal to the latitude required. 



PROBLEM XXVIII. 



The latitude of any place, not exceeding 66j degrees, being 

 given, tojind in what climate" the place is. 



Find the length of the longest day at the given place 

 by Prob. XXVI. and whatever be the number of hours 



Note 89. A climatt, from the equator to either of the polar circles, 

 U a tract of the earth's surface, included between two such parallel* 



