Errors of Types of Minimum Spirit Thermometers. 



421 



(column 1), follow closely the curve of corrections (column 7) 

 derived from simultaneous readings of the spirit and the mercurial 

 Standard ; while the sums of the residuals, irrespective of sign, 

 given in column 9, are greater than those in column ,3, whereas 

 they should be smaller if the corrections in column 7 are real. 



November 790S. 



1 2 3 4 5 6 7 8 9 /O // 12 /3 /4 /5 /6 /7 /S /9 20 21 22 23 24 25 26 27 28 29 30 



*10 



o 



-10 



\-20 



-/■o 







Corn 



idiom 



f Column 7 



i 



















































































































Re.sc 



duals 



(Colu 



nn .9 , 



i 































































































































































Fig. 1. 



In order to ascertain the reason for this undoubted connection 

 between the adopted corrections to the minimum temperatures as 

 recorded by No. 1,470, and the excess of the minima thus corrected, 

 over those obtained from the thermograms, the readings of the 

 spirit at Oh. (midnight) and 12h. (noon) during the three months 

 January to March, 1904, were compared with the corresponding 

 readings of the Kew Standard No. 714, and the differences tabulated 

 for steady falling and rising temperatures respectively. The results 

 are shown in Table II., p. 422. 



Summary. 



Temperatuke. Excess of Standard No. 714 over Minimum, Casella No. 1,470. 



Steady 85 observations - 0-21° 



Rising 47 observations + 0-10° 



Falling 48 observations - 0"51° 



In forming the above tables all available observations were 

 utilised. It will be seen that the correction to reduce the readings 

 of No. 1,470 to the Standard No. 714 is— 



+ 0-10° for rising temperatures, 

 — - 51° for falling temperatures, 



