NINETEENTH ANNUAL YEAR BOOK— PART X 529 



meadow larks on the 22d; Postville, robins on the 11th, blue birds on the 

 12th; Des Moines, robins on the 4th, wild geese on the lith and blue birds 

 on the 23d. Fog, 4th, 5th, 6th, 9th, 13th, 14th. 21st. 30th. Glaze, 9th. Hail, 

 9th, 13th. Halo (lunar or solar), 5th, 9th, 13th, 14th, 22d, 25th, 27th, 28th, 

 29th. Haze, 12th, 19th, 20th, 21st, 22d. Sleet, 7th, 8th, 9th, 13th, 14th. 

 Thunderstorms, 9th, 13th, 14th, 21st, 22d. 



Rivers. The rivers and streams broke up and ran out quietly, in the 

 southern part of the State near the close of February, in the central part 

 about the 6th of March, and in the northern part about the 18th. The 

 breaking up of the upper Missouri River caused stages within about 1.5 

 feet of flood stage at Iowa points on that river toward' the close of the 

 month. 



AURORA OF MARCH 7, 1918. 



One of the most spectacular displays of the aurora borealis ever ob- 

 served in this State occurred on the night of March 7th. Newspapers re- 

 port the display in nearly all portions of the United States and in north- 

 ern Europe. At Des Moines it became noticeable about 7:20 p. m. in the 

 form of an arch of light in the northern sky at an altitude of about 25°. 

 This rapidly enlarged, became brighter and rose to an altiude of 60° by 

 8 p. m., the width of the arch being about 20° and extending from the east- 

 ern to the western horizons. About this time the flickering streamers of 

 light known as "merry dancers" began to appear; also vivid colors, green 

 predominating in the north and northeast and crimson in the northwest. 

 About 9 p. m. large areas of light appeared in the south and gradually 

 formed a continuous arch of light at an altitude of about 30°, known as 

 the "auroral corona." At 9:30 p. m. the entire heavens were ablaze with 

 hues and shafts of light that rapidly changed into forms of endless va- 

 riety, the predominating thing being shafts of whiter light that rose from 

 the horizon at nearly all points except a small arc in the south, and con- 

 verged at a point a little, possibly 10°, southwest of the zenith. About 

 10:30 p. m. the display began to diminish, but some signs of it remained 

 as late as 1:30 a. m. of the 8th. At times the light of the aurora was 

 nearly equal to that of the full moon. Telegraph service was much troubled 

 by the magnetic effects of the aurora. 



Similar descriptions were received from observers in all portions of the 

 State. Mr. J. H. Spencer, Meteorologist, Weather Bureau, Dubuque, Iowa, 

 adds: "Another prominent feature was the many distinct patches or 

 groups of light, resembling thin, whitish clouds. They were most numer- 

 ous overhead and looked like cirro-stratus clouds of irregular shape. 

 There was a decided contrast between the clear sky and the cloud-like 

 patches. Where there were no patches the stars shone with much bril- 

 liancy, but through the cloud-like patches the stars shone only faintly." 



Prof. J. L. Tilton, Simpson College, Indianola, Iowa, states that, "Over- 

 head was what appeared to be a faint grayish cloud forming a band about 

 half way across the sky from east to west. This band slowly drifted 

 southward and faded away when across Orion. ***** if this was 

 a cloud it seemed related to the aurora in cause. Other bands of a similar 

 character appeared with some degree of regularity, several of them com- 



