548 



SCIENCE 



[N. S. Vol. XLV. No. 1169 



preferentially collect in the great nebulous 

 areas, or, in many cases, become enmeshed 

 in details of nebulous strvicture. We should 

 pause long and consider well before em- 

 barking uijon a voyage in that direction. 



Long centuries of ignorance as to our 

 surroundings gave way, finally, to the en- 

 lightening influence of the discoverj- of the 

 place of the continents upon the earth, 

 and of the place of our planet with respect 

 to the sun. Working at peace and under 

 extreme encouragement, the astronomers of 



to-day are learning the place of our star 

 and its planets amongst the other stars. If 

 the Magellanic Clouds, the greater globular 

 star clusters, and the spiral nebulfe prove 

 to be seisarate and independent systems, we 

 shall bequeath to our successors the mighty 

 problem of finding the place of our great 

 stellar system amongst the host of stellar 

 systems which stretch out through endless 

 space. 



Lick Observatory, 



University of Califorki.a. 



