410 Scientific Intelligence. 
Green 
ally very brilliant in Orange, and then it was possible to predict 
R 
its ‘Srnurewns to the unassisted e 
ount Lola we have Pies equently seen the heliotrope 
images ath the naked eye over the longest lines; and at Round 
Top Mountain, with lines reaching 160 “mile es, we saw zs Snow 
Mount heliotrope very plainly with the nake de eye upon several 
occasions. I am satisfied that the Mount Helena heliotrope would 
have been seen with the naked eye from Mount Shasta, 192 miles, 
in fa pine weather. Although the spectrum on such occasions 
is very vivid, the naked eye did not detect the color 
ormer paper I have woferrod to this phenomen on as a nor- 
eS) 
ore. 
ary amalgam-backed mirrors become whitish and 
opaque in a few days’ exposure, but the fine silver deposit on the 
glass retains its brilliancy unimpaired. 
I have established the iellowing: sizes for heliotropes, and have 
practienlly tested them up to 192 miles. I feel certain that the 
proportions may be carried to any pravionbid line on the earth’s 
ele 
9, %, all 
mies? cSt anh. AGeeal™” |) Rise) sSmrtage,| tae, | “usea” 
——— 
10 021 | O46) — 130 | 35°5 60 
13 0:36 | 0°60 | 0-4 138 63 | 5°6 too weak. 
20 084 | O92; — 141 | 42 65 6° weak. 
30 180.4 Pav 148 | 46 es 1 
40 3:36 | 1831 1 6° v. weak 
5n 525 | 2:3 | 3-Otoobright.|| 160 73 | 8 
e 155 | 28 3.0 169 | 60 1.7 - 
0 | 1028 | 3-2 3-0 ; : 
80 | 13-4 3°7 pie 192) 173 8°8 } 12° Small 
90 | 17 4°] re 200 | 84: 2 telescope. 
100 | 21: 46 aS: 250 | 131° 115 
107 | 24 49 5-0 300 | 189° 13°8 
‘ 5°0 weak. 
120 | 30 55 ‘ pb eeonr. 
5 Sey 
Pe ay Se 
