Registered at G.P.O., Wellington, as a Magazine. 
ART. 
THE v 
NEW ZEALAND 
JOURNAL OF SCIENCE 
AND 
TECHNOLOGY. 
\ 
Edited by ■ 
Dr. J; ALLAN THOMSON ; 
Assisted by 
Professor C. A. COTTON, Mr. S. H. JENKINSON, and 
Professor E. MARSDEN, Wellington, 
Professor A. P. W. THOMAS, Auckland, 
Professors C. CHILTON and R. J. SCOTT, Christchurch, 
and 
Professor W. B. BENHAM, Dunedin. 
Issued under the authority of the Hon. W, DOWNIE STEWART, 
Minister of Internal Affairs. 
vol. i iv— no. 4. August, 1921. 
WELLINGTON, N.Z. 
By Authority : Marcus F. Marks, Government Printer. 
1921. 
ANNUAL SUBSCRIPTION, 6s. SINGLE COPY, Is. 6d. 
CONTENTS ON PAGE 4 OF COVER. 
