Transportation Water and Air 



271 



Sails have been used for about six thousand years. At first 

 they were only for small boats. As they were fixed in position 

 they were dangerous in gusts of wind and useless if the wind 

 came from the wrong direction. Gradually man learned to make 

 sails that could easily be drawn up or lowered to meet the wind 

 conditions. By degrees these sails were more carefully designed 

 and were made adjustable to winds so that vessels could sail by 



Save "Old Ironsides' 



"OLD IRONSIDES" UNDER FULL SAIL 



U.S.S. Constitution, our most famous square-rigged ship. 



Fund. 



wind power even when the wind was not in the direction in 

 which they wished to go. Sea captains learned to sail by tacking, 

 zig-zagging by alternate moves first in one direction and then in 

 another, in order to take advantage of the wind. Masts and rig- 

 ging gradually developed further, and sails increased in number 

 and became more intricate until vessels like the famous "Old 

 Ironsides" came into being. These carried a wonderful mass 



