NAVIGATION 337 



matter than merely fixing them into dry ground. They suc- 

 ceeded, however, in completing their arduous task with simple 

 wooden and stone tools, joined their upright poles by means 

 of crossbeams ; and on the platform thus formed they built 

 their round or square huts with walls and floors of basket-work 

 and mud, joining their lacustrine settlements with the dry land 

 by means of easily moved wooden bridges. 



The terramara, a contrivance of the Bronze Age, consists of 

 a pile-built village on dry land surrounded by a wall, examples 

 of which are found in Upper Italy, Hungary and Bohemia. 

 The best explanation is that of Homes, who thinks that the 

 object was to protect the storehouses and sleeping-rooms 

 from beasts of prey, troublesome domestic animals, noxious 

 vermin, floods, etc., by raising them above the level of the 

 ground. They are comparable to the houses of many South 

 African and Papuan villages, which are raised on piles, the 

 only difference being that the latter are never surrounded by a 

 wall. 



Navigation. All races who live on the shores of rivers or 

 lakes are known to be proficient swimmers. It may therefore 

 be assumed that the inhabitants of the pile-villages chose their 

 lake dwellings owing to their familiarity with the water. But 

 in order to sink their piles and to command the water, they 

 must have had the means of travelling over it. We may 

 understand easily how man first came to think of conveying 

 himself in and steering a floating boat, when we consider how 

 often he must have chanced to see broken trunks of trees 

 floating in the water. If he swung himself on to one of them, 

 he would discover that the trunk would bear him, and if he 

 took a wooden pole in his hand he would find that with it he 

 could steer in any direction he desired. This would lead to a 

 new idea, namely, to bind together a number of trunks, and 

 so to construct a raft which should be steerable and carry more 

 than one person. Meanwhile, others would have discovered 

 that the hides of animals when inflated (Fig. 163) were able to 

 support considerable weights when placed in water. A stage 

 made of longitudinal and cross beams fastened to four inflated 

 hides, provided them with a ship able to brave all the billows ; 

 this could be steered either by means of a rudder attached 



22 



