180 THE RAINFALL AT BRISBANE. 
cycle, namely, from 1878 to 1885. The first and second cycles 
coincide in most months, as for instance January, April, 
May, July, August, September, and October very fairly. 
But, unfortunately, the limited number of years of obser- 
vations at my command, coupled with the length of their 
cycle, which as stated is between 18 and 19 years, leaves 
me no chance to complete the second or a third cycle to 
correct and establish their mean cycle. However, for this 
and the ensuing year of 1886 the rainfalls of the several months 
of the year should, according to my cyclar curves, approximately 
be as follows :— 
year. inches. 
October ici or emer 4 
November se A rticicht oa a Scores F 
December oe 1 gsiaiegals Sacto ea 3 
January IS86"....: 7 
February be deed ane 4a Seeman 6 
March fo. 28 Soe). eae ee 5s 
April 5 14 (a flood likely) 
May 8 1 
June SL a ee ee 5 
July gal ee ie es B 
August Ee no rain 
September * ic 
Total inches of rain for the 12 months 483 
As in the previous cyclar curves on Plate VIII., so in these 
monthly curves from the year 1880 to ’85, tendencies to 
fluctuate are very noticeable, remarkably so in January, Feb- 
ruary, March, June, July, August, November and, December ; 
but I anticipate that in future years those violent fluctuations, 
though within the precincts of the cycle, will cease and cling 
more closely again to the contours of the previous cycle, so ag 
to enable me to predict within reasonable limits, the meteoro- 
logical nature of each month of the ensuing year. 
Should encouragement and facility of obtaining data be 
offered, I intend to determine those cyclar curves also for our 
