54 LEWIS : 



from an}' given point within the area where the halos were 

 visible it is possible, indeed it is very probable, that the details 

 of the phenomenon would assume as many varied shapes and 

 forms as there were observers (taking into consideration dis- 

 tances), and from the very nature and causes of the halos, it 

 logically follows that local conditions would necessarily have 

 a material effect, more or less favorable, for a perfect observ- 

 ation of them. 



The elevation, at Media, from which the observations 

 were obtained as shown in Figure i, is 340.29 feet above mean 

 tide at Sandy Hook (Pennsylvania Railroad datum), and 

 was at a point very near 39° 55' North latitude and 75° 25' 

 West longitude. 



At 11.00 A. M. the sun's shadow was cast North 35° 00' 

 West. The axis of the poles of the halos was, therefore, 

 North 55° 00' East. The entire design formed by the display 

 was perfectly symmetrical about the line bearing in the same 

 direction as the shadow of the sun. The point of intersection 

 of the line bearing North 35° 00' West and the extreme outer 

 edge of the outer, or great halo (observations being taken 

 toward the southeast), was 20° 40' above the eastern horizon. 

 The intersection of the same line and the outside edge of 

 inner of small halo was discovered to be 44° 45' above the 

 horizon. The altitude of the sun was found to be approxi- 

 mately 70° 00' above the eastern horizon as measured on the 

 same line as were the readings on the halos. Ver}' satisfact- 

 ory results were in this manner obtained in determining the 

 distances of the two halos from the sun, and these distances 

 conform within a degree or two with the measurements as cal- 

 culated by the various authorities as to the angular distance 

 of the respective circles from the sun. The inner circle is 

 usually distant about 22° 00' from the sun, while the outer 

 halo is, according to the authorities, al^out 46° 00' away. It 

 is therefore evident that the phenomenon in question was in 

 this detail characteristic. 



The outer halo, it will be observed. Figure i, did not form 



