XXXIV GEELMUYDEN. ASTRONOMICAL OBSERVATIONS.  [NORW. POL. EXP. 
ee ee eee 
Sat. UL. Sat. IV. 
(ao R Ds al R 
1893.02 | 0.01666 | —0.01657 1895.23 0.01139 | —0.01142 
93.51 1182 1172 95.41 1738 1751 
94.00 1399 1392 95.60 2163 2180 
94.49 2059 2065 95.78 491 2508 
94.98 2762 2781 95.96 2738 O155 
95.47 3348 3372 96.15 2916 9999 
95.96 3740 3757 96.33 3028 3035 
96.45 3899 3902 96.51 3077 3078 
96.94 3819 3806 96.70 3063 3058 
97.43 3518 3494 96.88 2987 2978 
97.92 3035 3012 97.06 0.02852 | —0.02837 
98.44 0.02499 | —0.02414 
For the determination of the breadth of the invisible segment all obser- 
vations of disappearances and reappearances in the years 1893—98, published 
in the Monthly Notices and in the Astronomische Nachrichten, were exami- 
ned, and those selected where the same phenomenon had been observed by 
means of two or more telescopes of different aperture. Each pair of such 
observations gave an equation, which was retained in the form of equation 
(6) with @ (which depends on the apertures) as coefficient of #, though it was 
an unfavorable circumstance that most of the observations had been taken 
with instruments so far superior to that of the Fram in regard of size, that 
the weight of an equation was often much smaller than would have been 
the case with a somewhat larger standard aperture. Some few observations 
with large apertures differing only 1 or 2 cm. have been omitted. 
In the second column of the following Table a, containing the places of 
observation, the following abbreviations have been used: Bs Bermerside, Ch 
Christiania, Gr Greenwich, Gt Gottingen, Jn Jena, Ks Kasan, Ly Lyons, Po 
Pola, Ue Ucele, Ut Utrecht. In some cases two observations with telescopes 
of nearly the same aperture have been combined into one, which is indicated 
by an added 2 or by a+ between the places when they were different. Next 
follow the apertures A, and A, in centimetres. Owing to the not uncommon 
custom of giving, in astronomical publications, the aperture in inches of the 
different countries, even where the metrical system has been introduced, the 
last figure may in some cases be inaccurate; the fraction of cm. has been 
retained here only when certain, The last column contains the quantity 
10 ck (T,—T,) which is designated by +. 
