56 COSMOS. 



find that north of Greenland (Gruenllant), which is repre- 

 sented as belonging to the eastern portion of Asia, the north 

 magnetic pole is depicted as an insular mountain. Its 

 position was gradually marked as being farther south in the 

 reve Compendia de la Sphera, by Martin Cortez, 1545, as 

 well as in the Geographia di Tolomeo of Liveo Sanuto, 1588. 

 The attainment of this point, called el calamitico, was asso- 

 ciated with great expectations, since it was supposed in 

 accordance with a delusion, which was not dissipated till 

 long afterwards, that some miraculoso stupendo effetto would 

 be experienced by those who reached it. 



Until towards the end of the 16th century, men occupied 

 themselves only with those phenomena of variation which 

 exerted a direct influence on the ship's reckoning and the 

 determination of its place at sea. Instead of the one line of 

 no variation, which had been found by Columbus in 1492, 

 the learned Jesuit Acosta, who had been instructed by Por- 

 tuguese pilots (1589) expressed the belief in his admirable 

 Historia Natural de las Indias that he was able to indicate 

 four such lines. As the ship's reckoning, together with the 

 accurate determination of the direction (or of the angle 

 measured by the corrected compass) also requires the distance 

 the ship had made, the introduction of the log, although this 

 mode of measuring is even at the present day very imperfect, 

 nevertheless marked an important epoch in the history of 

 navigation. I believe that I have proved, although contrary 

 to previously adopted opinions, that the first certain evidence 

 of the use of the log 67 (la cadena de la popa, la corredera) 

 occurs in the journal which was kept by Antonio Pigafetta 

 during the voyage of Magellan, and which refers to the 

 month of January, 1521. Columbus, Juan de la Cosa, Se- 



57 Cosmos, vol. ii, pp. 631 634. In the time of King Edward III. of 

 England, when, as Sir Harris Nicolas (History of the Royal Navy, 

 1847, vol. ii, p. 180), has shown, ships were guided by the compass, 

 which was then called the sailstone dial, sailing needle, or adamant, we 

 find it expressly stated in the accounts of the expemes for equipping the 

 king's ship, "The George," in the year 1345, that sixteen hour-glasses 

 had been bought in Flanders ; this statement, however, is by no means 

 a proof of the use of the log. The ampolletas (or hour-glasses) of the 

 Spaniards were, as we most plainly find from the statements of Enciso 

 in Cespides, in use long before the introduction of the log, "echamlo 

 \juuto por fantasia in la corredera de los perezosos." 



