450 KANSAS CITY REVIEW OF SCIENCE. 



whose momemtum is almost nothing, the latter must necessarily be caught in our 

 atmosphere and carried along with us. If the repulsion between its particles 

 which had hitherto prevented condensation continued to exist, the filmy mass 

 would gradually spread through or over the earth's atmosphere, attending it as 

 an envelope for some indefinite period, perhaps ultimately to be wholly absorbed. • 

 This cosmical matter floating in the upper air or above it would doubtless affect 

 the sun's rays by reflection and refraction as well as directly obstructing them to 

 some extent. It might also modify the structure of the atmosphere itself so as to, 

 cause the ordinary constituents of the air to act differently in the transmission of 

 light. That it does constantly obstruct, decom[)Ose and reflect the sun's rays in 

 a considerable degree is plainly shown by several facts which are matters of com- 

 mon observation. 



ist. On all days when the sky is free from clouds or nearly so, the whole 

 atmosphere in the vicinity of the sun's direction and to the extent of sixty or 

 ninety degrees each way, including fully one half of the visible heavens, shows a 

 whitish haze of dazzling brightness near the sun and diminishing gradually in all 

 directions. On the clearest days this halo around the sun takes a more decided 

 form and color : immediately around the sun an area of intense whiteness, sur- 

 rounded by a broad ring of reddish brown color. Having spent the past sum- 

 mer on the dry plains of Dakota I have observed the above described appear- 

 ance very strongly marked throughout the season. 



2d. The portions of the sky more remote from the sun and opposite to it 

 have never, during the past twelve months exhibited the clear " ethereal blue" so 

 common and so beautiful in clear weather at all seasons of all preceding years. 

 It now constantly presents, at the brighest, but a dull bluish lead color, and 



3d. This condition is further shown by the following from the report in 

 Science, page 295, of the proceedings of the Astronomical Section of the Ameri- 

 can Association for the Advancement of Science at the recent meeting at Phila- 

 delphia. " One very interesting statement of Mr. Swift to the eff'ect that there 

 had not been a first rate clear sky since the red glows appeared a year ago follow- 

 ing the Krakatoa explosion, bears out the general experience of workers in other 

 observatories, especially those who try to see stars near the sun in the day-time." 



Whether this remarkable condition of the atmosphere can be reasonably sup- 

 posed to have any relation to the unusual continued mild and calm weather of 

 the present autumn, is an idea that readily suggests itself, though it may proba- 

 bly be but a mere coincidence. This and many other related questions are as 

 yet unsolved, and the whole subject has not by any means lost its interest. 



