4() 



between tlie curves for the mnntlis of tlie year 1880 witli those for the year 

 1879, considerable irregularity will be observed. This irregularity is most 

 marked in the summer months; thus, in June 1880 most of the rains came from 

 the North and Northeast while in June 1879 the greater number catne from the 

 South and 8<iuthwest. For the winter niuiiths the curves show a diflferenoe in 

 magnitude rather than in direction, althongli tliey also show a general shifting 

 from the Northwest to the North. 



The second diagram of chart Number \C> is (juite similar in form to the 

 corresponding curve for 1870. Both show three maximum rainy ]ieriods, the first 

 in February or Blarch, the second, and by fvr the greatest in June and the third 

 in October. The inconstancy of the rainfall in the summer months is strongly 

 shown, however, in that Tnly, which re j)resents a minimum point in the curve 

 for 1879, almost reaches the greatest maxinunn in 188() an<l September becomes 

 a minimum instead. 



Table R siiows the mean percentage i>f humidity for every day in the year 

 and table S gives the mean and maximum and minimiuu for the months. The 

 mean percentage of liumiility for the year was 76.6, the lowest ob.served being 31. 

 Although much rain fell in Jtme the maximum percentage of humidity observed 

 was 97. In the hourly ol)servations, however, for that month a saturated atmos- 

 ])here is recorded on several occasions. In tlie Ib-st diagram of chart Number 17 

 the variations in the actual force of tlie vapor for tlie various months is shown and 

 in the second the fluctuations in the mean percentages of humidity are exhibited. 

 It will be seen that the real force of vapor is much greater during the summer 

 months than during the remainder of the year and also that, notwithstanding 

 the increased temperature, the relative humidity is also, in general, greater 

 during the sunmier months. 



