1918.] The N.Z. Journal of Science and Technology. 
307 
At every withdrawal a measured volume of water was taken, and the zinc 
chloride estimated by titration with standard silver nitrate. From this 
the quantity of salt in solution was computed. The rate of removal of 
salt from the timber was shown graphically by plotting the percentage of 
chloride against the time in weeks. 
After thirty-one weeks the amount of leaching had fallen to such an 
extent as to be negligible, and it was found that the green wood had lost 
27 per cent., while the seasoned wood had lost 19 per cent. ZnCl 2 . It will 
be seen that under these drastic conditions some 25 per cent, of the salt 
is leached out within the first twenty weeks, the greatest loss being in the 
first six weeks. 
Time—Weeks. 
Fig. 8.-—-Diagram showing leaching of zinc chloride from Fagns Menziesii. 
Acknowledgments .—In conclusion, I should like to record my appre¬ 
ciation of the assistance given me by the following gentlemen : Mr. Arnold, 
foreman of McCallum’s Southland Milling Company; Mr. Eamsay, of 
Keith Ramsay (Limited) ; and Mr. McNair, Assistant Railway Engineer 
for Otago. Without their help it would have been difficult, if not im¬ 
possible, to present any results of practical value. 
APPENDIX. 
Note on New Zealand Beeches (commonly called “ Birches ”), 
by E. Phillips Turner, F.R.G-.S. 
Feigns Solandri —The most common name of this tree is “ black-birch,” 
but it has several other names. In the Wellington and Marlborough dis¬ 
tricts it is called “ black-birch ” ; in Canterbury it is called “black-birch,” 
“white-birch,” “red-birch,” and “ brown-birch ” ; in Otago it is known as 
“ white-birch,” “ black-birch,” or “ black-heart birch.” Young specimens 
of this tree that have no dark heart-wood are often called “ white-birch.” 
This tree is a beech, and it would do away with confusion if it was called 
“ black-beech.” 
Fagus Menziesii. —The commonest name of this tree is “ silver-birch,” 
but it is also often called “ brown-birch,” “ red-birch,” and “ white-birch ” 
