452 ARCHITECHNICS. 



been attributed to Daedalus ; but, on this point, nothing certain is 

 known. The Phoenicians improved the art of ship building ; and 

 constructed vessels of greater size and strength. Sailyards, are said 

 to have been invented 1240 B. C. ; and anchors were used as early 

 as 700 B. C. ; previously to which, vessels in harbor were either 

 stranded, or secured by halsers. The Romans dedicated their ships 

 to particular divinities ; and built some few vessels of enormous size. 

 The invention of the Compass, already alluded to under magnetism, 

 (p. 362), and especially the extension of voyages to the Indies, and 

 to America, in pursuit of wealth, led the Spaniards and Portuguese to 

 a bolder style of ship building, which was adopted and farther im- 

 proved by the English. The ships built two or three centuries ago, 

 were very high at the ends, and liable to bend, or become broken- 

 backed. The theory of mechanics was first thoroughly applied to 

 ship building, by Paul Hoste, in a work published at Lyons, in 

 1696; and this theory has been farther extended by Navier, in 

 France ; Atwood, in England ; and Chapman, in Sweden. 



The first project of Steam Navigation, worthy of notice, appears to 

 have been that of Jonathan Hulls, of England ; who, in 1736, proposed 

 the construction of a steam tow boat, with paddles at the stern. In 

 1781, the Marquis Jeffroy, or Jouffroy, is said to have built a steam 

 boat at Lyons, in France. In 1783, Rumsey of Va. conceived the 

 plan of a steam boat, propelled by the reaction of a current of water, 

 forced through the boat, in a cylinder extending its whole length: 

 and he actually built a boat on this plan. In 1787, Mr. Fitch built a 

 steam boat at Philadelphia, moved by vertical oars at the sides, and 

 with considerable effect. The first boat actually propelled by steam, 

 in England, was built by Symington, in 1788, with paddles at the 

 stern. The project of propelling a boat by means of paddle wheels 

 at the sides, was suggested by Oliver Evans of Philadelphia ; and 

 actually executed by him in 1804. But all these attempts were con- 

 sidered, by the world at large, as failures : and it was reserved for 

 our countryman Fulton, to demonstrate the utility of steam naviga- 

 tion; by constructing, in 1807, a boat which made regular voyages, 

 from that time onward, between New York and Albany. This 

 improvement was not adopted in Great Britain, till the year 1812. 

 The first voyage across the Atlantic, by steam, was made in 1819, 

 by our countryman, Capt. Rogers ; and the present system of trans- 

 atlantic steam navigation, which commenced in 1838, forms a new 

 era in this art, if not in the history of the world. 



We shall treat briefly of Navitecture, under the heads of Ship 

 Building, Ship Rigging ; and Steamboats. 



S 1. The process of Ship Building, requires accurate drawings; 

 which are often made on a large floor, and of the full size of the vessel. 

 The drawing in elevation, is called the sheer plan ; and gives the 

 height and appearance of the ship as seen from one side. The cross 

 section, showing the ship as seen from behind, is called the body 

 plan ; and a drawing of the ship, as seen from above, is called the 

 deck plan, or half-breadth plan. These drawings presuppose a 

 thorough knowledge of this art; as of the displacement of water 

 by the ship ; its centres of gravity and buoyancy ; its stability or 



