MR. W. N. SHAW ON HYP.ROMETR1C METHODS. 



103 



Mean dew-point 12'42 



Correction ..... ... '22 



Observed dew-point 12*20 



Difference from theoretical . . i '06 



The impression that is left on the mind by observations with the instrument is a 

 sense of insecurity and want of confidence in the observations, that is sometimes 

 followed by surprise at the concordance of the reading with the theoretical dew-point, 

 and the closeness with which the indication of the dew-point follows any change in 

 the temperature of the saturator, as, for instance, in the example just quoted, where 

 the saturator readings rose from 12 0> 18 C. to 12 0- 33 C., the dew-point readings 

 followed from 12'08 C. to 12'28 C. 



20. The other two assumptions referred to in 18 may be tested by the accuracy 

 of agreement of the final dew-point readings deduced from the observations with the 

 theoretical dew-point given by the saturator, and the chemical method. The results 

 of the comparison for a number of observations are given in the following table ; the 

 numbers of the experiments are the same as those of Table VI. 



TABLE VIII. 



