Errors of Types of Minimum Spirit Thermometers. 



427 



The coefficient of sensitiveness was then computed on the 

 assumption that the relation between the constant temperature r 

 of the comparison bath, the reading t of the thermometer at any 

 time 0, and the coefficient of sensitiveness X is represented by the 

 equation — 



db + ^ " '> = °' " 



the solution of which gives — 



(t-r) = (t - t)(T** 9 



where t is the value of t when = 0. 



Curves were drawn from the data contained in Table IV., and 

 values of t read off at intervals d = d x , d 2 . . . 6 n , the unit interval 

 being 6 seconds. Substituting the values of t and d thus found in 

 the expression given above, and taking t and r from Table IV., we 

 obtain the following solutions for X for the several thermometers. 



Ther- 

 mometer 





No. 714. 







No. 1,470. 





Series 



1st and 2nd combined 



1st and 2nd combined 



t 



T 





 79-50 



66-75 



80-17 

 66-50 



9 



sees. 

 6 



sees. 

 12 



sees. 

 18 



sees. 

 6 



sees. 

 36 



sees. 

 66 



sees. 

 96 



t 

 X 



70-80 

 •191 



68-00 

 •194 



67-16 

 •191 



77-85 

 •031 



70-93 

 •031 



68-30 

 •031 



67-10 

 •033 



Mean X 



0-192 



0-031 



Ther- 

 mometer 



No. 45,535. 





























Series 



1st 



2nd 



3rd 



to 



T 



o 

 81-5 

 67-0 



o 

 81-0 

 67-0 







79-5 

 67-0 



e 



sees. 

 6 



sees. 

 24 



sees. 

 42 



sees. 

 60 



sees. 

 6 



sees. 

 24 







72-8 

 •037 



sees. 

 42 







70-4 

 •034 



sees. 

 60 



69-2 

 •031 



sees. 

 6 



o 

 77-0 

 •037 



sees. 

 24 







72 5 

 •034 



sees. 

 42 



o 

 70-4 

 •031 



sees. 

 60 



t 



X 



o 

 78-3 

 •042 



o 

 73-0 

 •037 



o 

 70-5 

 •034 



o 



69-1 

 •032 



o 



77-9 

 •042 



69-2 

 •029 



Mean X 



0-036 



036 



0-033 



Chree's "Notes on Thermometry," Phil. Mag., 1898. 



