THE RAIN-FALL IN THE UNITED STATES. 



COLLECTION AND TABULATION OF RECORDS AND RESULTS. 



It is intended in the following pages to present, as a contribution towards the 

 advancement of American climatology, the leading facts connected with the aqueous 

 precipitation over the area of the United States ; also to include such scanty records 

 from other parts of North America and from Central and South America as could 

 be collected. It has been the aim to bring together from all sources records of 

 observations of the fall of water, in rain or snow, from the earliest observers to 

 those of the present time. 



The first work, after collecting the material, was to form tables giving a sum- 

 mary of monthly amounts of rain-fall, arranged for each State and Territory 

 separately, for each year. These tables served as the basis from which most of the 

 deductions given in this memoir are derived ; but, on account of their voluminous 

 character and consequent great expense of printing, they are not published at pre- 

 sent. They can be referred to, however, at the Institution, for more minute infor- 

 mation 1 respecting the nature of the record than could conveniently be given in 

 the printed tables, which contain all that is known or essential to the true valua- 

 tion of each series. Tables A and B of this memoir are directly derived from 

 these manuscript tables, and present their general contents in a more condensed 

 form. 



As early as 1853 and 1854 the Smithsonian Institution had collected a large 

 number of rain records, and tabulated the monthly and annual amounts, and given 

 other information respecting the rain-fall for stations occupied up to that period. 

 This collection was placed in my hands in August, 1867, was revised and enlarged, 

 and the records and results, generally, were brought up to the close of the year 

 1866. As no definite limit for closing the records was assigned, the tables at many 

 stations include those for the year 1867, and, for some few localities, those for a 

 part of 1868 also. Additions to any of the tables can readily be made hereafter, 

 as date and reference are given for each series. 



1 In these manuscript tables any break in the regularly noted series for any month is indicated by 

 dashes, and when there was no precipitation during the interval a zero is inserted. In the monthly 

 summaries the insertion of a star (*) indicates incomplete record, the sign (f) indicates a doubtful 

 result, and the sign (J) an approximate result. The series of Smithsonian records of 1860 were in 

 part lost or damaged by fire, in January, 1865; many of these, however, have since been replaced 

 by the observers when called upon for duplicates. 



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