EUCALYPTUS TREES. 53 
products from heated wood, and the various appa- 
ratus employed in dry distillation, reference may be 
made to the great work, Chemistry Applied to Arts 
and Manufactures, by Professor Muspratt, a man of 
genius and industry, whose death within the last few 
months we had so deeply to deplore. 
Presented to you here are samples of tar, acetic 
acid, and alcohol, from several of our more common 
woods ; also pieces of pine-wood, coated with euca- 
lyptus tar, the black color, with its fine lustre, have 
remained unimpaired fora series of years. Our wood- 
tar would, for many industrial purposes, be equal in 
value to the best kinds of other tar, and may prove, 
in some respects, superior to them. 
Among the undeveloped wood-resources we must 
not pass that referring to potash, particularly as this 
alkali can be obtained without sacrifice of any valua- 
ble timber, and from localities not accessible to the 
wood trade. 
For the preparation of potash, the wood, bark, 
branches, and foliage are burnt in pits sunk three or 
four feet in the ground ; the incineration is continued 
till the pit isalmost filled with ashes. Young branch- 
es and leaves are usually much richer in potash than 
the stem-wood ; hence they should not be rejected. 
The ashes thus obtained are placed, in tubs or casks, 
on straw, over a false bottom. 
Cold water, in moderate quantities, is poured over 
the ash, and the first strong potash-liquid removed 
for evaporation in flat iron vessels, while the weaker 
fluid is used for the lixiviation of fresh ashes. 
While the evaporation proceeds, fresh portions of 
strong liquid are added until the concentrated boil- 
ing fluid assumes a rather thick consistence, 
