JOURNAL 



OF THE 



WASHINGTON ACADEMY OF SCIENCES 



Vol. V MARCH 4, 1915 No. 5 



PHYSICS. — Length standards and measurements^ Louis A. 

 Fischer, Bureau of Standards. 



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, material- 

 ize, and when I was finally compelled a few weeks ago to select 

 a subject, I naturally selected the subject which is announced 

 on your program because that is the one with which I am most 

 familiar. 



While many attempts have been made to trace the origin of 

 our earlier standards of length, and volumes have been written 

 upon the subject, I think it may be said that very little is known 

 about the subject, which for that very reason lends itself to 

 speculation. The Book of Genesis mentions the cubit as being 

 in use before the Flood; and in the early history of Egypt we 

 find mention of two different cubits which appear to have been 

 in use. The question as to the values of these standards at one 

 time engaged the attention of no less a personage than Sir 

 Isaac Newton, who in a dissertation on cubits gave it as his 

 opinion that the longer of the Egyptian cubits was equal to 20.7 

 English inches and that the sacred cubit of the Jews was equal 

 to 24.7 inches. 



1 Presidential address before the Philosophical Society of Washington on 

 January 16, 1915. 



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