JOURNAL 



OF THE 



WASHINGTON ACADEMY OF SCIENCES 



Vol. VI APRIL 4, 1916 No. 7 



ASTRONOMY.— The distances of the heavenly bodies. 1 W. A. 

 Eichelberger, U. S. Naval Observatory. 



A year ago our retiring president took the members of the 

 Society into his confidence as follows: 



Cognizant of the fact that my election to the presidency of the 

 Philosophical Society a year ago, obligated me to give an address of 

 some sort one year later, I confidently waited for the inspiration that 

 I felt would suggest a fitting subject for the occasion. The expected 

 inspiration did not, however, materialize. 



Undoubtedly because of that fact, and out of the goodness 

 of his heart, towards the close of his address he turned to the 

 present speaker, then presiding, and said: 



I have said nothing whatever about the determination of the dis- 

 tances between the planets nor of the units used by astronomers in 

 reckoning distances of the stars. . . . They form, so to speak, 

 other chapters of the subject which I shall leave to some future ex- 

 president of our Society. 



This call, I suppose, was intended to take the place of an 

 inspiration, and wherever I have gone during the past twelve 

 months the call has ever been ringing in my ears. The subject 

 of the evening is presented therefore not as a matter of choice but 

 from compulsion. 



Before any attempt was made by the ancients to determine 

 the distance from the Earth of any celestial body, we find them 



1 Presidential address before the Philosophical Society of Washington on March 

 4, 1916. 



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