Nitrogen Thermometer from Zinc to Palladium. 129 

 Table IV. — Estimated Errors and their Effect on the Value oft. 



Quantity 



Source of 

 error 



Amount of error 



Effect on t 



affected 















at 400° 



at 1500° 



at 400° 



at 1500° 





Temperature 











(A) Temperature 



differences 











of gas 



over bulb 













surface 



2mv. 



5 mv. 



± 0-2° 



+ 0-4° 





Variability 







1 mv. 







+ o-r 



(B) Po 



Eeference 













point 



0-02 mm. 



0-02 mm. 



± 0-04° 



± 0-15° 



• c< 



Manometer 













setting 



0'02 mm. 



0-02 mm. 



± 0-04° 



± 0-15° 



" 



Scale correc- 













tions 



0-01 mm. 



0-01 mm. 



± 0-02° 



± 0-07° 



It 



Temperature of 













mercury 



O'Oomm. 



0'05 mm. 



± 0-10° 



± 0-38° 



It 



Barometer 













setting 



0-03 mm. 



0-03 mm. 



± 0-06° 



± 0-23° 



i I 



Temperature 













of barometer 



0*05 mm. 



0*05 mm. 



± 0-10° 



± 0-38° 



" 



Variations 













in_p 







0--05mm. 







Oto ±0-3 



p 



Reference 













point 



0-02 mm. 



0-02 mm. 



± 0-02° 







" 



Manometer 













setting 



0*02 mm. 



0-02 mm. 



± 0-02° 







" 



Scale correc- 













tions 



0-02 mm. 



0-02 mm. 



± 0-02° 







ti 



Temperature 













mercury 



0-07 mm. 



0-20 mm. 



± 0-07° 



± 0.05° 



( i 



Barometer 













setting 



0-03 mm. 



0-03 mm. 



± 0-03° 



± 0-01° 



" 



Barometer 













temperature 



0-05 mm. 



0-05 mm. 



± 0-05° 



± 0-01° 



" 



Unheated \ v x 

 space J ti 



0-020 cc. 



0-020 cc. 



± 0-07° 



± 0-5° 



■ 



0-5-50° 



0-5°-100° 



± 0-01° 



±o-r 



(3 



Temperature 



1-0° 



2-0° 



± 0-02° 



± 0-11° 



a 



Expansion 



0*005 mm. 



0-008 mm. 



± 0-02° 



±0-09 



" 



Hysteresis in 













expansion 



0-01 mm. 



0-01 mm. 



±0-04° 



± 0-10° 



(C) E.M.F. 



Instrumental 













correction 



1 mv. 



2 mv. 



± 0-1° 



± 0-2° 



<l 



Contamination 







0-12 mv. 







Oto +1-0° 



" 



Integration 













over bulb 



3 mv. 



12 mv. 



± 0-3° 



± 1-0° 



(D) Fixed points 



Instrumental 













corrections 



1 mv. 



2mv. 



±0-1° 



± 0-2° 



n 



Contamination 







0-10 mv. 







Oto -1-0° 



a 



Variation in 













given charge 



Specific : 



-lOmv. 



Specific 0-1 -1*0° 



" 



Variation be- 











tween differ- 











ent charges 



Specific 1 



- 20 mv. 



Specific 0-1 -2-0° 



