38 H. G. SMITH. * 
The Table No. II gives the percentages of phosphoric 
acid, lime, and magnesia, in the ashes of a few representa- 
tive species of distinct groups of Hucalypts. It was a 
difficult matter to completely burn the woods of the little- 
lime-containing species, like E. macrorrhyncha, E. pilularis, 
etc., as the ash was so readily fusible, this being due to the 
large amount of potash and other alkalis present. It might 
be thought, therefore, that these species would produce an 
abundance of potassium carbonate when burned, but unfor- 
tunately the total mineral contents in their timbers is. 
remarkably small, as can be seen from Table I. With the 
‘* Boxes ’’ the ash is almost entirely lime, with little mag- 
nesia, and there seems to be a remarkable agreement in 
this respect with species of the several groups which have 
closelyfagreeing botanical characters. It is in the members 
of this group, particularly the species which contain the 
aldehyde aromadendral in their oils, that the greatest 
amount of oxalic acid seems to be: formed, so that the 
abundance of lime in these trees may be necessary to com- 
bine with the excess of this acid. The alkalis in this group 
appear to be just as small in amount as the lime is abundant; 
in the ash of H. albens the potash (as K,O) was 1°64 per 
cent., and this represented practically the whole of the 
alkalis present. It is thus not feasible to obtain potassium 
carbonate in quantity by burning the timbers of this group 
of Eucalypts. With the ‘‘Ironbarks”’ the lime is still in 
considerable amount, and the magnesia relatively increas- 
ing. Tbe alkalis in this group, although greater in amount | 
than in the “‘ Boxes,’’ do not appear to much exceed 25 per 
cent. of the total mineral constituents. The amount of 
magnesia in the ash-like timbers of EH. Delegatensis and 
EK. regnans is remarkable, even exceeding the lime in this 
respect, and the lime and magnesia taken together repre- 
sent—as carbonates—about three-fourths of the entire 
mineral constituents of these trees, consequently the alkalis 
