116 WHEAT PRODUCTION IN NEW ZEALAND 
Zealand. A gradual rise in total production took place 
until 1883-4 when a maximum was reached, after which 
in the succeeding two years production falls away 
rapidly. These are the circumstances of a typical credit 
cycle. At first, trade is depressed and progress is slow. 
Then comes a period of rapid expansion followed by 
sudden collapse, and trade once more becomes depressed. 
So our cycle from 1877-1886 may be divided into three 
periods :—the first, 1877-80, when progress was slow 
but sure; then a period of rapid expansion, 1881-4; 
followed thirdly, by a sudden collapse in 1885-6. 
3. 1887-1895.—The third eycle, this time of nine 
years, is no less conformatory to Jevons’s cyclical theory 
than the former period. Here, again, during the years 
1887-91 production gradually increases until a culmin- 
ating point is reached in 1892, after which there is a 
decline at first slow and then rapid until 1895. 
4. 1896-1902—.A somewhat shorter cycle then follows, 
but nevertheless typical in its nature. A steady recovery 
from 1895 sets in, and in 1899 a maximum is reached, 
after which once more production declines. 
5. 1602-1913.—Since 1902 cyclical changes are not so 
definite. The wheat industry, gradually losing its position 
as one of our principal industries, is consequently in a 
ten or eleven year periods—of the sun spots, which were con- 
sidered to reflect changes in the amount of heat given by the 
sun. His son, Prof. H. S. Jevons, continued the thesis by 
making extensive investigations into fluctuations in the agri- 
cultural produce of the United States of America, the results 
of which are set out in the article quoted above. 
In this way he established a trade cycle of about 103 years 
with three interacting cycles within the period of 34 years. 
This is what is known as a typical Jevonian cycle. In order 
to test the validity of the theory in reference to New Zealand 
it would be necessary to consider the whole of the primary 
produce of the Dominion, which is rather beyond the scope of 
this investigation. 
