16 INTRODUCTION. 



Prob. 4. The Latitude of any Place being given, to find alt those 

 Places that have the same Latitude. 



, x p n The globe being rectified (a) according to the lati- 



* ' " tude of the given place, and that place being brought 



to the brazen meridian, make a mark exactly above the same, and 

 turning the globe round, all those places passing under the said 

 mark have the same latitude with the given place. 



Prob. 5. Two Places being given on the Globe, to find the Distance 



between them. 



If the places are under the same meridian, that is, have the same 

 longitude, their difference of latitude, reckoning 69^ miles to a de- 

 gree, will give the distance. 



If they have the same latitude, but differ in longitude, their dis- 

 tance may be found by their difference of longitude, reckoning the 

 number of miles in a degree of longitude in their common parallel 

 of latitude, according to the table given above. 



If they differ both in latitude and longitude, lay the graduated 

 edge of the quadrant of altitude over both the places, and the num- 

 ber of degrees intercepted between them will give their distance 

 from each other, reckoning every degree to be 69^ English miles. 



Prob. 6. To find the Sun's Place in the Eclifitic at any Time. 



The month and day being given, look for the same upon the 

 wooden horizon ; and over-against the day you will find the sign 

 and degree in which the sun is at that time; which sign and de- 

 gree being noted in the ecliptic, the same is the sun's place, or 

 nearly, at the time desired. 



Prob. 7. The Month and Day being given, as also the particular 

 Time of that Day, to find those Places of the Globe to which the 

 Sun is in the Meridian at that Time. 



The pole being elevated according to the latitude of the place 

 where you are, bi'ing the said place to the brazen meridian, and 

 setting the index of the horary circle at the hour of the day, in the 

 given place, or where you are, turn the globe till the index points 

 at the upper figure of XII ; which done, fix the globe in that situa- 

 tion, and observe what places are exactly under the upper hemis- 

 phere of the brazen meridian ; for those are the places desired. 



Prob. 8. To know the Length of the Day and Night in any Place 

 of the Earth at any Time. 



, . p Elevate the pole (a) according to the latitude of 



th\ p H ° B fi the given place ; find the sun's. place in the ecliptic 

 \b) rROB. . ^ at that t j me . wn j ch b e i n g brought to the east 



side of the horizon, set the index of the horary circle at noon, or 

 the upper figure of XII : and turning the globe till the aforesaid 

 place of the ecliptic touch the western side of the horizon, look up- 

 on the horary circle ; and where the index points, reckon the num- 

 ber of hours to the upper figure of XII; for that is the length of 

 the day ; the complepient of which, to 24 hours is the length of the 

 night. 



