248 WEIGHING OF 



We can not afford to take conclusions ei ready made'* by 

 authorities at Washington or at Berlin; we have to be 

 convinced by the facts, and not by the apparent forms of 

 accuracy and the official dictum. 



And seeing, that the means of a liter of oxygen actually 

 vary to the extent of mgr. according as it is contained in 

 one or another globe; 



and seeing, that the weight of a liter of oxygen is de facto 

 varying to a full milligramme in different determinations in 

 three series (II first, III first and second) ; 



ive must admit these facts as the true limit of the accuracy 

 attained, 



although Mr. Morley may imagine that he has attained 

 to the precision of his " probable error" of one-twentieth of 

 the milligramme! 



Morley has determined the -weight of a liter of oxygen with 

 an uncertainty of one milligramme at best in any one of these 

 series. 



But how much is this weight, to the nearest milligramme ? 



Why, that is rather uncertain, again. Let us see. We 

 will give both Morley's own means, and ours rounded off at 

 the proper place. 



Weight of One Liter of Oxygen, in Grammes. 



Mean 1.42 9 41 



We notice a distinct and gradual increase in the weight, 

 from the first to the last series of Morley; the total change 

 amounting to almost half a milligramme. 



These are the actual scientific results; the "fifth" deci- 

 mal is imagination, pure and simple. 



Morley's Weighings of Hydrogen. 



We must next consider Morley's weighings of hydrogen. 



He gives his results to the millionth of the gramme per 

 liter; that is the thousandth of the milligramme. 



Wonderful, truly wonderful, is the precision of Morley's 

 work on paper. 



Turning to page 63, where the 19 determinations of his 



