IN THE MADRAS PRESIDENCY. 63 



the colonists is being largely imported into Scinde and Ceylon ; 

 and Mr Acworth intimated to me that he had entered into a 

 contract for 7000 Jarrah sleepers. It is important to watch this 

 experiment, as the result is of the first moment, no wood having 

 hitherto been found to resist white ants (Termites), combined with 

 exposure to heat and moisture. A timber trade with Australia 

 would benefit the colony, and supply the Indian market with a 

 substitute for teak, which is yearly becoming more scarce and 

 Costly. The first cargo of yarrah has arrived from Swan Eiver. 

 Some species of Eucalyptus are considered half hardy in the south 

 of England ; and as there are many fine specimens on the Nil- 

 giri Hills, and a few at Bangalore, there is reason to hope that 

 these valuable trees may succeed on our mountain-ranges, and 

 furnish a timber superior to any of the indigenous woods. It has 

 recently been proposed to substitute sleepers of cast-iron for 

 those of wood, and the plan has already been carried out on a 

 large scale ; it is thought that iron will in the end be found the 

 most economical material for sleepers. 



Trenails and Wedges. — The Indian woods which appear to be 

 best adapted for these purposes are Kara-marda (Terminalia 

 glabra), and Sal (Vatica rdbusta) ; the former for trenails, the 

 latter for wedges. Sal is a hard wood, possessed of considerable 

 elasticity, and resists the attacks of white ants. These woods 

 should have a second seasoning after they are manufactured, as 

 there is a material shrinking immediately after the piece has 

 been cut out of the log and shaped. The ends of the trenails 

 should be dipped in tar as a precautionary measure. 



7. The Preservation of Timber. — In an economical point oi 

 view, this subject is of the greatest importance. Eailway 

 sleepers, which ought to have stood five or six years at least, 

 have been found useless after being laid down not more than 

 one-third of that time ; in fact, there are some parts of the 

 Madras line where it was necessary that they should be taken 

 up and replaced before the district itself was completed. The 

 durability of woods is affected by a variety of causes, and their 

 liability to rapid decay may be prevented by certain precautionary 

 measures : — 

 (1.) Season of Felling. — The sapwood is the portion of the tree 



