22 



being given. Then wore tliree days in tlie year in each of which the total 

 amount of wind exceeded fonr Inindred miles. They were February 2S, Jlarch 

 20 and October 4. If the barometric curves be examined at these dates it will 

 be seen, of course, that these high winds were preceded or accompanied by a 

 rajiid and considerable fall in the barometer, the miiiimTuii barometric height 

 for the year occurring at 7 a. m. on March 20, the day on which the maximum 

 number of miles of wind is recorded. The minimum amount of wind recorded 

 on any single day in the year was 34.7 miles on 3Iay 19 and the smallest amount 

 for any month was 32S8.9 miles in the month of September. 



Tables K, L, and M, exhibit the winds classified as to direction and velocity. 

 Table L shows the classitication of the winds exceeding twenty miles per hour 

 in velocity, according to direction, for all the months of the year. From this 

 it will be seen that on 83 occasions the wind was recorded as reaching a velocity 

 of twenty miles or more. By comparison with the corresponding tables for the 

 year 1879 it appeare that high winds were more frequent during this year than 

 the last, in about the ratio of two to one, the number recorded for last year 

 being 4(3. A very similar distribution will be observed, however, as to direction 

 and also as to time. The same marked excess of these winds from the North 

 ami Northwest is shown in both tables. During the year 1880, out of a total of 

 83 liigh winds, Gl are recorded from the North and Nnrthwest; in 1879 the 

 number was 30 out of a total of 40, the ratio being almost exactly the same. 

 Concerning these two directions, however, the proportion for 1879 is reversed in 

 ISSO, by far the greater number being recorded from the Nortli. An examina- 

 tion of table M, which shows the classification of the total miles of wind as to 

 time and direction, proves that the largest part of the atmospheric movement is 

 from the same direction. Out of a total of ;'J3279 miles of wind during the year, 

 28791 miles, or something more than one half came from the North and North- 

 west. In 1879 the proportion was slightly less than one half. Both of these 

 tables, in connection with table K, show the excess, in both velocity and 

 frequency, of winds from the Nortii and Northwest. 



A clearer conception of these facts, however, can bo obtained by an 

 examination of charts numbered from 5 to 10 which have been construct- 

 ed to represent the distribution of winds as to direction and time, according 

 to the metliod described in the last report. Some peculiarities of these diagrams, 

 to which atteuti(in was called in the last report, are again repeated in the 

 curves for 1880. In chart number 5, which cxhiliits the prevailing direc- 

 tions for the months of the year, there is the same appearance of a shifting 

 of the wind from the North to the South through the East during the 

 months of Jlay, -lune, and July, and the same sudden change from South winds 

 in August to North winds in September. Indood, if the general chart ibr the 

 Year, number 7, l>e compared with the corresponding chart for 1879. it will be 

 seen to resemble it very closely, about the only dill'erence being dne to the tact 

 that winds from the North exceeded in number those from the Northwest to a 



