1917] METEOROLOGY. 115 



The conclusion Is reached that " a forecast of the size of the cotton crop, 

 based on the ginning reports, has a much greater value when consideration 

 is given to the influencing weather factors. . . . than when the reports 

 alone are considered. For example, if temperatures during the critical months 

 of growth be high and thus conduce to a rapid advancement and early ma- 

 turity of the crop, and in addition the weather be favorable for picking during 

 the period covei-ed by a given early ginning report, say September 1 to Septem- 

 ber 25, it may be safely considered that the percentage of the total crop 

 ginned during the period will be much in excess of the average and the final 

 yield less than that apparently indicated by the actual amount ginned to 

 that date. . . . 



" If, however, these modifying weather influences work in opposition and 

 thus largely neutralize each other then the amount ginned, whether above or 

 below the average, gives a better direct indication as to whether the final yield 

 will also show values above or below the average than in the other case. 

 Furthermore if the temperature conditions were unfavorable for early maturity 

 and the percentage of fair days during the ginning period small, it may be 

 safely assumed that the final yield will be larger than apparently indicated 

 by the actual amount ginned. 



" In studying early ginning reports in connection with the two modifying 

 weather factors under discussion, it must be borne in mind that temperature 

 has the dominating influence and should be given greater weight, but later, 

 say for the period from September 25 to October IS, the amount of fair weather 

 during the period itself takes precedence. . . . 



"The fact that favorable temperatures during the early growing season are 

 also conducive to comparatively large yields, as well as to early maturity of 

 the crop, should likewise be considered, and it might also be noted that early 

 maturity, In effect, postpones the date of first killing frost in fall by an equal 

 number of days represented by the earliness of the crop and thus reduces the 

 chance of damage from this source." 



Monthly Weather Review {U. S. Mo. Weather Rev., ^5 {1911), Nos. 1, pp. 1-J^6, 

 pis. 10, figs. 2; 2, pp. 47-90, pis. 10, figs. S).— In addition to weather forecasts, 

 river and flood observations, and seismological reports for January and Feb- 

 ruary, 1917 ; lists of additions to the Weather Bureau Libi-ary and of recent 

 papers on meteorology and seismology ; notes on the weather of the months ; 

 solar and sky radiation measurements at Washington, D. C, during January 

 and February, 1917; condensed climatological summaries; and the usual cli- 

 matological tables and charts, these numbers contain the following articles : 



No. 1. — Notes on the Horizontal Rainbow, by S. Nakarnura ; Demonstration 

 of Horizontal and Intersecting Rainbows, by K. Otobe ; Aurora of August 26, 



1916, Observed at Hessel, Mich., by F. E. Nipher ; Relation of Weather to the 

 Amount of Cotton Ginned during Certain Periods (illus.), by J. B. Kincer 

 (see p. 114); Grasshoppers at Sea, by W. E. Hurd ; National Meteorological 

 Service of Colombia; Another "Dark Day of May 19, 1780"? Classification 

 of the Hydrometeors, II, by G. Hellmann ; Notes and Comments on Hellmann's 

 Classification of Hydrometeors ; Alternate Deposition of Rauhreif and Rauhels 

 (illus.), by W. R. Blair; and Ammonia in Dew (see p. 116). 



No. g.— The Smoke Cloud and the High Haze of 1916, by H. H. Kimball; 

 Free-air Data In the Hawaiian Islands, July, 1915, by W. E. Ellis; Weather 

 Bureau Exhibit at the First Pan American Aeronautic Exposition (illus.), by 

 W. R. Gregg; Sound Areas of the Explosion at East London, January 19, 



1917, by C. Davison; Parhelic Circle with Two Pairs of Parhelia at Fargo, 

 N. Dak. ; Competency of Wind in Land Depletion, by C. R. Keyes ; Reduction 



