THE QUALITY OF WHEAT 69 
factors; first, the percentage of dirt, weed seeds, and 
other impurities ; secondly, the percentage of water in the 
sample; and, thirdly, a complex and somewhat ill-defined 
character, commonly called ‘‘strength.’’ 
(a) Impurities—The first factor is not very important 
in New Zealand, for under the methods of growing, 
cleaning, and threshing practised here, a practically 
clean sample is produced. The threshing machine used 
generally throughout the country separates the sheaf 
into six parts, straw, short straw, chaff, dust and small 
weeds, ‘‘seconds’’ or shrivelled and broken grain, and 
finally ‘‘firsts’’ or clean wheat fit for milling. It will 
be easily seen that this classification gives a good, clean 
sample. In some foreign countries, however, this is far 
from the actual state of affairs. Indian and Russian 
wheats contain a great percentage of impurities, which 
render them in this respect relatively inefficient from the 
miller’s point of view. 
(b) Percentage of Moisture.—The percentage of 
moisture, the natural moisture as it is usually called, 
varies greatly in the different producing countries. 
English wheats contain about 16 per cent. of moisture, 
rising in wet seasons to 18 per cent. In Russia the per- 
centage is about 12, which is the average for Canada, 
United States, and Argentina; while in Australia and on 
the arid lands of the Pacific Coast of North America 10 
per cent. is about the average. New Zealand wheats 
contain relatively high moisture percentages. Pearl in 
normal seasons has a moisture content of from 15 to 16 
per cent., according to the tests made over a series of 
years by a local miller; while Tuscan and Hunter’s go 
as high as 16 to 17 per cent. In wet seasons these per- 
centages may be increased to 17 for Pearl, and 18 for 
Tusean and Hunter’s, which is considerably higher than 
the percentage for most of the exporting countries. 
The importance of the percentage of water arises from 
