PREFACE 



This collection of data is published in response to the need expressed 

 by the following resolution passed by the International Meteorological 

 Conference in session at Utrecht in September 1923: 



RESOLUTION 



13. (4) V. Considering Professor Exner's proposal about the calculation 

 of the correlations between weather-anomalies in regions far from each other, 

 the Conference thinks that publication of long and homogeneous series of 

 observations in the form of monthlj' means of pressure, temperature, and 

 rainfall would be of the highest importance for the study of the general 

 circulation of the atmosphere. This publication should comprise a small 

 number of stations at a mutual distance of 500 to 1000 kilometers, preferably 

 belonging to the Reseau Mondial, and if these should fail, other stations with 

 a longer homogeneous series. It proposes that the various meteorological 

 institutes should establish such series up to the year 1920 and invites the 

 following gentlemen to see to the execution of this Resolution. 



Dr. Walker for the stations of Asia ; 



Prof. Exner for the stations of Europe; 



Mr. Clayton for the stations of America ; 



Dr. Simpson for the stations of Africa, Australia and the oceans. 



Meteorology stands deeply indebted to Mr. John A. Roebling for 

 providing the means to publish this long-desired collection of funda- 

 mental data, which cannot but be of great use in future theoretical and 

 practical researches. 



