Feb., 1918] Cattle Temperament 133 



RESULTS. 



Treatment. — After sufficient data had been collected, (about 

 150 curves), a method of interpreting the pneumographic 

 tracings was used, whereby respiratory activities and the 

 corresponding variations were taken into account. The ampli- 

 tude of each inspiration and expiration was measured in milli- 

 meters, and these measurements were tabulated statistically, 

 and the data plotted in the form of a frequency polygon, 

 where the amplitudes of respirations were plotted against 

 their frequencies. The mean (M), standard deviation (S. D.), 

 coefficient of variability (Cv.), and their corresponding probable 

 errors, were calculated according to the usual formulae. 



Many such frequency polygons were made of the different 

 subjects, under different conditions, and taken from different 

 days selected at random. After a sufficient number of such 

 polygons from each animal were plotted, the entire number of 

 polygons of each individual under a given condition, were 

 constructed into a composite curve or polygon, which latter 

 was taken as characteristic of that animal under the given 

 condition. The composite was constructed in the following 

 manner. The means of the individual polygons were super- 

 imposed upon each other, and then each polygon was plotted 

 about its own mean. Then, for example, where the various 

 lines of amplitude 4 crossed the different frequency lines, a 

 simple average was taken, and this average represented the 

 average frequency of amplitude 4, and was plotted as such 

 upon the composite. From the composite, another set of 

 figures was derived, and this taken as characteristic of the 

 given subject under the given condition. And so the mean, 

 standard deviation, and coefficient of variability of the com- 

 posite were taken as representative. This method of con- 

 structing composites was made necessary by the curious moving 

 of the mean up or dow^n (see below), and by variations in 

 pressure in the pneumograph and tambour due to changes in 

 tension and positions of the same. 



