426 pliny's natueal history. [Book XVI. 



there are trees, of which ships are built, the wood of which 

 has been found uninjured at the end of two hundred years, 43 

 even if it has been under water all that time. They say, also, 

 that in the same island there is a certain shrub, 43 about the 

 thickness of a walking-stick only, and spotted like a tiger's 

 skin : it is very heavy, and will break like glass if it happens 

 to fail upon a hard substance. 



CHAP. 81. (42.) — THE WOODS USED IN BUILDING. 



"We have in Italy some woods that are apt to split of 

 themselves : to prevent this, architects recommend that they 

 should be first seasoned in manure 44 and then dried, in order 

 to render them proof against the action of the atmosphere. 

 The woods of the fir and larch are well adapted, even when 

 used transversely, for the support of heavy burdens ; while the 

 robur and the olive are apt to bend and give way under a 

 weight. The wood of the poplar and the palm are also strong, 

 but this last will bend, though in a manner different from 

 the others ; for, while in all other instances the wood bends 

 downwards, in the palm it bends in the contrary direction, 43 

 and forms an arch. The woods of the pine and the cypress 

 are proof against decay and all attacks of wood- worm. The 

 walnut is easily warped, but we sometimes see beams even 

 made of it. It gives warning, however, before it breaks, by a 

 loud cracking noise ; such was the case at Antandros, at the 

 public baths there — the bathers took the alarm upon hearing 

 the beams crack, and made their escape. The pine, the pitch- 

 tree, and the alder are employed for making hollow pipes for 

 the conveyance of water, and when buried in the earth will 

 last for many years. If, however, they are not well covered 

 over, they will very soon rot ; and the resistance they offer to 

 decay will increase in a most surprising degree if the outer 

 surface as well is left in contact with the water. 



42 There is nothing very surprising in this, as most woods are preserved 

 better when completely immersed in water, than when exposed to the va- 

 riations of the atmosphere. 



« He borrows this fable from Theophrastus, B. v. c. 5. 



* 4 This process, Fee says, would be attended with no success. 



< 5 It is not quite clear whether he intends this observation to apply to the 

 poplar and the palm, or to the last only. It is true, however, in neither 

 case, and is contrary, as Fee observes, to all physical laws. 



