136 



5. Ashes. These include E. gigantea (E. delegatensis). E. fraxinoides, 



E. Sieberiana, E. oreades. 



6. Blackbutts. E. patens, the W.A. Blackbutt, is added to the eastern 



E. pilularis. 



7. Mahoganies — 



(a) Pale (E. acmenioides and E. umbra.) 



(b) Red (E. resinifera, E. marginata (Jarrah) ). 



8. Boxes — 



(a) Pale. This is made to include E. Boormani, E. microtheca, E. bicolor 



(which are certainly not pale. J.H.M.). 



(b) Red. This is made to include E. Bosistoana and E. populifolia 



(which are certainly not red. J.H.M.). 



9. Bloodwoods. 

 10. Peppermints. 



1919. — " The Hardwoods of Australia and their Economics," by R. T. Baker. 



In this work the classification of 1917 does not appear to have been disturbed, 

 but at p. 5, a classification, based on colours, is introduced (see Colours below), and at 

 p. 383 one of grades of hardness. 



Colours. 



Although colours have already been casually referred to, there is a practical 

 convenience in giving the literature of the subject as regards colours, so far as I know it. 



The comparison of the colours of timbers is not easy, since sometimes they are 

 noted when newly cut, and sometimes when seasoned. As a rule, the timber is judged 

 as regards colour when seasoned, but, if the colours when fresh could be ascertained in 

 addition, the records would be more useful. Some of the colours of timbers are appar- 

 ently discrepant because the freshly cut timbers of some are compared with the colours 

 of seasoned timbers of others. At the same time, I have quoted colours of freshly cut 

 timbers whenever I could ascertain them. 



The colour of timber usually darkens and gets duller with age. As a rule, the 

 timber of a young tree is paler in colour than that of an older one. 



A chemical investigation of Eucalyptus timbers from the point of view of 

 presence or absence of colouring matter has not, so far as I am aware, been undertaken. 



I have briefly referred to colouration under Barks in Part LII, p. 104, and the 

 colour of the inner bark is frequently transmitted more or less to the timber. 



What is known as Heartwood consists of dead cells, the cavities of which as a 

 rule are blocked up by gums or other substances which, being more or less saturated 

 with tannins, are usually of a dark colour. 



