158 PROCEEDINGS OF SECTION B. 
In the two first instances the solutions percolated in under 
20 minutes; in the case of No. 4, thetimetaken was 2 hours; 
and this variation in the time of percolation would corre 
spondingly affect the results, which are probably low as 
regards oxidation, in the case of No. 1 at any rate. 
As an ordinary tailings heap contains a considerable per- 
centage of particles which would pass through a 100-mesh 
sieve, and a small amount of very much finer material, the 
above results afford a partial explanation of the exceedingly 
rapid consumption which takes place when KCN solutions 
are run on to a dry ore. 
As the cyanate formed during percolation must obtain 
the necessary O from the air in the void-spaces between the 
particles, the amount of O present is readily determined ; 
and, assuming the O and N are in the ordinary propor- 
tions in the tube, the following results are obtained :— 
Wt. of O 
corresponding| Vol. of O in | Vol of total | Vol. of total Degree of 
to Cyanate | ce. at NTP. | gases in tube.) void in tube.| Compression 
formed. 
grains. Ce: ce. ce. Atmosphere. 
“0039 2°72 9°06 9307 1°00 
"0054 | 3°76 12°53 9°97 1°25 
°0075 | 5°22 17°36 9°99 1°73 
-0078 5°44 18°13 9°99 i-sl 
THE CHEMISTRY OF -THE EUROPEAN, ASIAN, 
AND NEW ZEALAND SPECIES OF CORIARIA. 
By Prof. EasterrieLp, M.A., Ph.D., and B. C. Aston. 
[ Abstract. ] 
1. Coriaria myrtifolia (Southern Europe) has been shown 
to contain ellagic, gallic, and tannic acids, a yellow glucoside, 
together with a highly toxic glucoside coriamyrtin (Reban, . 
1866). 
2. The three New Zealand species of coriaria are con- 
sidered the most poisonous plants in that Colony. They 
~ contain the same acids as the European species, and the 
- same colouring,matter, but the toxic principle is a new glu- 
coside tutin, perfectly similar in pharmacological 
_action, but slower in producing the physiological effects. 
