90 Scientific Proceedings, Royal Dublin Society. 
Grove A (STELLAR Distances). 
The last group is that of stellar distances. These are most 
conveniently measured in metro-sixteens. 
The four units we have found it most convenient to use in” 
dealing with large magnitudes are very simply related to one 
another, as appears from the following list of them. 
The unit we have found it convenient 
t ren Deer aliaaact ae Hxampuers or MeasureD 
o use for geographical distances is Greuzan Disnincees 
stage, the stage being ten kilems or 6} EXPRESSED In Merro- 
miles. SIXTEENS. 
The unit for the distances of satellites _ (2#e Sud-section Aw provides 
5 : cee Sor all of these.) 
from their primaries is the Harth quadrant, 
the quadrant being 1000 stages. Group A. 
The unit for the distances of planets STELLAR Disrances. 
(ae ees De enn 
from the sun is the metro-ten, the metro- 
ten being 1000 quadrants, which is the = ; : 
ona 0 i) : oo q 
same as a million stages. El kK ee 
The unit for stellar distances is the ¢ 1 "i e 
metro-sixteen, the metro-sixteen being a 2) 6 B |2 
million metro-tens, or one billion stages. iM) = = |r 
The position which the metro-sixteen, Aw 
billion stages, occupies is indicated on : < 
Sve Ses ome O 000 000 000 O 
the table. Light in the open ether takes 
1-056 year (nearly a year and three weeks) | | 
to travel a metro-sixteen, so that the OneMetro-sixteen, | 1 
Distance at which par 31 
metro-sixteen is a little more than what, Bre ee ei ae 
in astronomy, has sometimes been called | Gane : lA 
the “light-year.” 61 Cygni,...: 6 
The distances of the nearest stars,  Sirtus, ......./8 
a liyre,...... 1 5 
those few of which the parallax can be 
directly measured, fall within Aw, the “that can be a1 9/9 
certained by pea 
sub-section of smallest stellar distances, allax, . 
as appears from the examples shown in | | | 
fig. 4. Fic. 4. 
Thus Aw includes the distances of the nearest stars along with 
sub-stellar distances, that is, distances from the Sun to stations 
between the solar system and the nearest star. Such sub-stellar 
intervals probably exist between the stars of a cluster. 
1 See foot-note on p. 84. 
