24 REPORT OF THE SECRETARY. 



ment of this kind is not effected, it becomes the duty of the Institution 

 to continue the sj'Stem with such improvements as the appropriation 

 ■which can be made on account of it will allow. During the past year 

 the number of stations has remained about the same, viz, 514, to which 

 a large number of additional rain-gauges have been distributed. Besides 

 these, meteorological observations are received from British America, 

 Central ximerica, Mexico, Bermuda, and some of the West Indies. 



The tables and deductions of rain-fall have been printed, and are 

 nearly ready for distribution. 



The discussion of alfthe observations relative to the winds made under 

 the direction of the Institution is still going on under the supervision 

 of Professor CofBn. Like his former work on the winds of the northern 

 hemisphere, it will consist mainly of abstracts of observations on the 

 relative frequency of the different winds, both at the surface of the earth 

 and in the higher regions, as indicated by the motion of the clouds, with 

 their resultant directions, and the monsoon influences by which they are 

 aflected in the different seasons, or months of the year. Where data 

 could be obtained the actual transfer of the air in miles is also given. 



Where the places of observation are sufficiently remote from each 

 other to admit of distinct delineation of the results, on maps of the scale 

 it is proposed to use, seiiarate computations are made for each ; in other 

 cases they are grouped by districts. The work will embrace the follow- 

 ing material : 



I. All the observations reported to the Smithsonian Institution from 

 the year 1854 to 1869, inclusive, with some others in the earlier years.. 



II. All those made at the United States military posts, and reported 

 to the Surgeon General, from the year 1822 to 1859 inclusive; and all 

 those from posts west of the Mississippi for the succeeding ten years, 

 np to the end of 18G9. 



III. All those at sea, collected at the United States Naval Observa- 

 tory, so far as they have been published ; i. e., over all the oceans be- 

 tween the parallels of latitude 60° north and south, except a compara- 

 tively small i)ortion of the Xorth Pacific lying between the meridians 

 150° east and 165° west from Greenwich ; and a few additional obser- 

 vations south of Cape Horn. 



IV. Those taken at sea, beyond these limits, by Arctic and xVntarctic 

 explorers. 



V. Those at several hundred stations in other parts of the globe. 

 This material, though very much more condensed than in his former 



work, will still make a considerably larger volume. 



In the discussion the whole surface of the earth is divided into zones 

 by i)arallels of latitude drawn 5° asunder, and observations in these zones 

 investigated in regular order from the North to the South Pole ; com- 

 mencing with the observations in each at the 180th meridian from Green- 

 wich, and proceeding easterly to the same meridian again. Profes- 

 sor Coffin hopes to complete the tabular work in the course of two or 



