METEOROLOGY — WATER. 417 



September and October, 1913, river and flood observations, lists of additions 

 to the Weather Bureau library and of recent papers on meteorology, a condensed 

 climatological summary, climatological tables and charts, and notes on the 

 rivers of the Sacramento and Ix)wer San Joaquin watersheds during the months 

 of September and October, 1913, by N. R. Taylor, and on streams and 

 weather of the Upper San Joaquin watershed, by W. E. Bonnett; these numbers 

 contain the following special papers : 



No. 9. — Relation of precipitation to tree growth, by M. N. Stewart (see 

 p. 445) ; Thunderstorm at Charleston, S. C, September 9, 1913, by J. H. Scott; 

 The Storm of September 3, 1913, in Eastern North Carolina, by L. A. Deiison; 

 The September Hot Wave in Los Angeles, Cal., by F. A. Carpenter; and Notes 

 on the Severe Heat and Drought Over the Middle West During the Summer of 

 1913 (illus.), by P. C. Day et al. 



No. 10.— Heavy Rainstorms of 1913 at New York City, by C. D. Reed ; Tor- 

 nadoes in Wisconsin on October 10, 1913, by W. R. Bormann; Rainfall and 

 Spring Wheat (illus.), by T. A. Blair (see p. 418) ; The Tornado of October 

 9, 1913. in Nebraska, by G. A. Loveland; The Tornado of October 9, 1913, at 

 Lebanon. Kans., by E. Y. Bower; Heavy Rains and Resultant Floods in South- 

 western Louisiana September 26 to October 4. 1913, by I. M. Cline; Storms in 

 Southeastern Louisiana October 23, 1913, by I. M. Cline; and A Meteorological 

 Study of Parks and Timbered Areas in the Western Yellow-Pine Forests of 

 Arizona and New Mexico (illus.), by G. A. Pearson. 



A return to normal atmospheric transparency, H. H. Kimball {Jour. ir«.s7/. 

 Acad.Sci., 4 (1914), No. 2, pp. 11-25, fig. i).— This paper presents evidence 

 derived from observations at Mount Weather, Va., relative to the gradual pre- 

 cipitation from the air of dust from the Katmai Volcano, June 6 and 7, 1912. 



Summarizing the results, it is stated that " pyrheliometric and polarimetric 

 observations unite in indicating a gradual increase in atmospheric transpar- 

 ency since the marked minimum in August, 1912. This increase is probably 

 due to the precipitation from the atmosphere of the dust that was introduced 

 into high levels by the eruption of Katmai Volcano in June, 1912. 



"At the same time, the solar and the antisolar distances of the neutral points 

 of Babinet and Arago, respectively, indicate that there may still be traces of 

 this dust in the upper atmosphere. 



" The duration of the Katmai dust cloud appears to have been less than the 

 duration (2 years) of the dust cloud that followed the eruptions of 1902-03. 

 and markedly less than the duration (3 years) of the dust cloud that fol- 

 lowed the eruption of Krakotoa in 1883." 



For notes on the effect of these dust clouds uiK)n temperature and evapora- 

 tion at the earth's surface, see previous articles (E. S. R., 29, p. 720). 



The Ohio and Mississippi floods of 1912, H. C. Frankenfield {U. S. Dept. 

 Agr., Weather Bur. Bui. Y, pp. 25, pis. 42). — This bulletin notes the extent of 

 the Mississippi drainage basin, the causes and frequency of Mississippi River 

 floods, and reports the origin, progress, duration and crest stages of the 

 Mississippi and Ohio floods of 1912. Comparative data of crest stages show 

 that new high water marks were established from Cairo to New Orleans, 

 except in the vicinity of Vicksburg where a higher stage was prevented by 

 crevasses. 



Data from the 1912 flood and floods in 1903, 1897, and 1882 show a steady 

 increase in flood height below Cairo without a corresponding increase in quan- 

 tity of precipitation, which is attributed to the influence of levees. Since the 

 duration of the 1912 flood was also greatest, it is concluded to be relatively 

 the most important. 



