236 TIMBER AND TIMBER TREES. [chap. 



climate like tliat of India, or to such a variable one as 

 that of England, very naturally ruptures from unequal 

 shrinkage, being also exposed to very great changes of 

 temperature. To obviate this peculiarity and apparent 

 defect, let the Jarrah be fallen when the sap is at the 

 lowest ebb, and flitched as previously suggested."* 



I have seen it stated in some correspondence from 

 Western Australia that a specimen of Jarrah timber has 

 been chemically examined by Professor Frankland, with 

 the view to ascertain whether there is any peculiar acid 

 or other substance present in it calculated to resist the 

 attacks of the Teredo navalis. It does not appear, 

 however, that anything of the kind has been found 

 which could be credited with the effect referred to. It 

 is believed by the Professor that the singular immunity 

 from attack which this wood enjoys is due either to the 

 odour or taste it possesses. These, though by no 

 means remarkable or repugnant to the human senses, 

 are probably strongly so to the Teredo navalis.f 



* The Committee of Lloyds have recently had the subject of Jarrah under 

 their consideration, and determined to class this timber with those in line 3, 

 Table A, of the Society's rules ; thus ranking it with Cuba Sabiou, Pencil 

 Cedar, &c. , for the construction and classification of ships. 



+ A late Western Australian almanack says : ' ' None of the neighbouring 

 colonies possess timber of a similar character to the Jarrah, or endowed with 

 equally valuable properties. If cut at the proper season, when the sap has 

 expended itself and the tree is at rest, it will be found the most enduiing of all 

 woods. On this condition it defies decay ; time, weather, water, the white ant, 

 and the sea-worm have no effect upon it. Specimens have been exhibited of 

 portions of wood which had been nearly thirty years partly under water and 

 partly out. Others had been used as posts, and for the same period buried in 

 sand, where the white ant destroys in a few weeks every other kind of wood. 

 For this peculiar property the Jarrah is now much sought after for railway 

 sleepers and telegraph posts in India and the colonies. It is admirably adapted 

 for dock gates, piles, and other purposes, and for keel-pieces, keelsons, and 

 other heavy timber in shipbuilding. Vessels of considerable burthen are built 

 entirely of this wood, the peouliar properties of which render copper sheathing 

 unnecessary, although the sea-worm is most abundant in these waters." 



