12 



and all work of naval architecture exposed to sea-water : it 

 moreover resists the attacks of termites, and on this account is 

 extensively employed in India for railway sleepers. 



The timber of Eucalyptus rostrata, Schlechtendal the Red 

 Gumtree (but not the red gumtree of Western Australia, which 

 is widely different), possesses the properties ascribed to Eucal- 

 yptus marginata, almost in an equal degree. 



As many may feel interested in knowing what the yield of 

 Potassa is from these trees, I have selected from my determina- 

 tions of Potassa in a variety of indigenous trees, such as had 

 reference to the Eucalypts, and embodied the results in the fol- 

 lowing Tables I, II, and III. 



I also submitted a number of the native woods to destructive 

 distillation, determining the percentage yield of charcoal, tar, 

 and crude wood-vinegar, and again, in the latter the proportion 

 of wood-spirit, acetic acid and other constituents : as in the former 

 instance, such as have reference to the Eucalypts have been se- 

 lected, and the results given in adjoining Tables IV and V. 



The woods employed were thoroughly air-dried, the amouu 

 torrefied in each case 25 pounds. 



