88 Analysis of certain Woods of Tasmania. 



the plant, bine, leaves, and flower, showing from the elements 

 of which these various portions of the plant were composed, 

 the amount of inorganic matter withdrawn from the ground 

 by every crop. From these analyses it appeared that a large 

 amount of potash was withdrawn annually in the flowers of 

 the hop alone, supposing the leaves and bine to be returned 

 to the ground, as would of course be the case. 



It occurred to me that it would be desirable to ascertain 

 the amount of wood ashes which it might be necessary to 

 mix with a compost for hops, in order to restore to 

 the ground the proper quantity of potash ; and for this pur- 

 pose I requested Dr. Motherwell to make some experiments 

 in order to ascertain the relative amount of potash in some 

 of the woods of the Colony. Dr. Motherwell very kindly 

 complied with my request ; and after carefully experimenting 

 upon some of the most common woods of the Colony, trans- 

 mitted to me the accompanying paper, containing not only 

 the results, but also the detailed statement of the mode in 

 which the experiments were conducted. By this it would 

 appear that the she-oak and the white gum, particularly 

 the former, are the trees which contain the most potash. 



While, however, these experiments are conclusive as far 

 as they go, it would be very desirable that some attempts 

 should be made on a large scale to ascertain the amount of 

 the ordinary potash of commerce which can be extracted 

 from the ashes of the different v,'oods by lixiviation and 

 evaporation in the ordinary manner. The operation is very 

 simple, and the apparatus required may be cheaply and 

 easily procured. The timber is heaped together in large 

 stacks, and burnt ; the ashes are then collected and placed 

 in wooden cisterns, having a plug at the bottom of one of 

 the sides, under a false bottom (a cask would answer the 

 purpose) ; a moderate quantity of water is then poured on 

 the mass of ashes, and some quick lime stirred in. After 



