54 SCIENCE OF THE MIDDLE AGES. PT. n. 



turned the basin the needle carried the card round till the 

 N. of the needle pointed to the north, and the s. to the 

 south, and from the other marks on the card he could then 



tell the direction of the west, 

 north-west, etc. 



It is easy to see how im- 

 portant this discovery was ; for 

 when a ship is at sea, far from 

 land, there is nothing to guide 

 m . , FlG ' 6 ' . the captain except the stars, 



t lavio s Compass floating on water. ' 



and they cannot always be 



seen, so that before he had a compass he was obliged to 

 keep in sight of land in order to find his way. But as soon 

 as he had an instrument which pointed out to him which 

 way his ship was going, he could steer boldly and safely 

 right across the sea. 



There has been much dispute as to who first discovered 

 the compass, and some people think that the Chinese used 

 it in very early times ; but learned men now agree that 

 Gioja discovered it independently, and it is certain that he 

 was the first to use it in a ship. Of course it would have 

 been very inconvenient to have it always floating in a basin 

 of water ; so the card was fitted, by means of a little cap, 

 on to the top of a pin, round which it could turn easily, 

 and this is the way it is still made. As the king of Naples 

 of that day belonged to the royal family of France, Gioja 

 marked the north point of the needle with a fleur-de-lys in 

 his honour, and the mariner's compass of all nations still 

 bears this mark. The territory of Principiato, where Gioja 

 was born, has also a compass for its arms, in memory of 

 his discovery. 



Invention of Printing, 1455. Before we go on to 

 speak of the wonderful voyages which followed the inven- 



