92 Analysin of certain Woods of Tasmania. 



quantity of potassa (say 3 draclims), making together 

 6 drachms of nitrate of potash for every 100 ounces of 

 wood consumed where the saturating power has been equal, 

 as in 2, 3, 4, 5, 6, 7 ; but in No. 1 the alkali is in larger 

 proportion, \^ ounces having required |- fluid ounce of 

 nitric acid to saturate, or G drachms of dry acid, making 

 the produce 1 2 drachms nitrate potash. 







Ih. oz. 



oz. 



dr. 





No. 1. 



She-oak reduced to asbes . . 



.. 12 8, 



or 200, 



produce 30 nitrate, 



or J per cent. 



No. 2. 



Black wattle „ 



.. 12 8 



„ 200 



24 „ 



? " 



No. 3. 



Silver wattle „ 



. . 12 8 



„ 200 



.. 24 



i » 



No. 4. 



White gum tree „ 



.. 12 8 



„ 2(10 



26 



4 2-18 



No. 5. 



Red Kum „ 



.. 12 8 



,. 200 ■) 







No. 6. 



Honeysuclde „ 



..6 4 



„ 100 



Alkali not tried. 





No. 7. 



Stringy barkj „ 



.. 12 8 



,. 200, 







Nos. 1 and 4 contain the most alkali. 



Manipidation. 



1. Cut the wood in small pieces to facilitate the drying; 

 weigh a decimal portion, and dry by a slow but regular 

 heat ; when perfectly dry, re-weigh and mark down the loss 

 by the evaporation of the fluids ; make up the loss, so as to 

 have 100 parts net ; if lbs. 4ozs. is weighed, it is equal to 

 100 ounces, or 100 parts. 



2. Proceed to destructive distillation by charring ; then 

 reduce the carbon to ashes in a free current of atmospheric 

 air to supply the requisite oxygen ; take out the residuum, 

 and when cold pass it through a fine hair-sieve to separate 

 any heterogeneous matter, or pieces of carbon nut reduced 

 to ashes, which put back into your calcining or charring 

 vessel, and continue the fire until the whole is reduced to 

 ashes ; add this to the first quantity, and weigh very care- 

 fully to ascertain the quantity of ashes. 



3. Proceed to lixiviatiou by adding boiling water to the 

 ashes in the proportion of 4 parts water to 1 of ashes, which 

 will take up all the soluble salts. 



4. Saturate with strong nitric acid as long as any efler- 

 vescence takes place, or until the test-paper (litmus) turns 



