94 EPOCHS IN THE HISTORY OP THE CONTEMPLATION OP 



All that in the course of time has contributed to favour 

 these advances in the art of navigation; the compass, and 

 the more correct knowledge of the magnetic declination, 

 the measurement of a ship's way by the more exact appara- 

 tus of the log, the use of chronometers and of lunar dis- 

 tances, the better construction of vessels, the substitu- 

 tion of another propelling force for the force of the wind, 

 and in all respects, the skilful application of astronomy to a 

 ship's reckoning, must be regarded as powerful means of 

 throwing open all parts of the earth's surface, of accelerating 

 the animating intercourse of nations with each other, and 

 of advancing the investigation of cosmical relations. Taking 

 this as our point of view, we would here recal the fact that 

 as early as the middle of the 13th century "nautical instru- 

 ments were in use for determining time by the altitudes of 

 stars" in the vessels of the Catalans and of the Island of 

 Majorca; and that the astrolabe described by Raymond 

 Lully, in his Arte de Navegar, is almost two centuries older 

 than that of Martin Behaim. The importance of astrono- 

 mical methods was so vividly recognised in Portugal, that 

 about the year 1484 Behaim was named president of a 

 Junta de Mathematicos, "who were to compute tables of 

 the sun's declination/' and, as Barros says, ( 451 ) to teach 

 pilots the " maneira de navegar per altura do sol." The 

 navigation "by the meridian altitudes of the sun" was 

 already at that period clearly distinguished from the naviga- 

 tion by determinations of longitude, or "por la altura del 

 este-oeste." ( 452 ) 



The desirability of fixing the locality of the Papal line of 

 demarcation, for the sake of settling the boundary be- 

 tween the claims of the Spanish and Portuguese crowns in 



