M. Greenwood 
71 
5. Influence of Special Diseases on the Cardiac Biometric Constants. 
We are now in a position to consider the effect of some special diseases on the 
weight and correlations of the heart. Unfortunately, scantiness of material and 
pressure on my time hindered my developing this most interesting branch of my 
subject very fully in the present paper. I shall hope to give it further con- 
sideration in another communication. I have confined my attention here to the 
heart and spleen weights, variabilities, and correlations in the case of two disease 
groups. First, Pneumonia (excluding tubercular disease) ; secondly. Valvular 
Disease of the Heart and Aortic Aneurism. I regret that the total number of 
cases available is small. 
TABLE XI. Hearts and Spleens. Cases of Pneumonia. Number 177. 
Meau Heart 12-50 ozs. Standard Deviation 2768 ozs. 
Mean Spleen 6'59 ozs. Standard Deviation 2-842 ozs. 
Correlation of Heart and Spleen = -1065 ± -0501. 
TABLE XII. Hearts and Spleens. Cases of Valvular Disease and Aortic Aneurism. 
Number 166. 
Mean Heart 19-08 ozs. Standard Deviation 5-950 ozs. 
Mean Spleen 8-57 ozs. Standard Deviation 5-158 ozs. 
Correlation = -0552 ± -0522. 
Forming as before a table for relative variabilities : 
TABLE D. 
Relative Variabilities of Heart and Spleen under Special Diseases. 
Disease 
Organ 
Coefficient of 
Variation 
Pneumonia 
Heart 
22-15 
Valvular Dise 
ise and Aortic Aneurism 
Heart 
31-18 
Pneumonia 
Spleen 
43-12 
Valvular Disef 
ise and Aortic Aneurism 
Spleen 
60-16 
From these values of the constants we may draw the following conclusions : 
(a) In cases of pneumonia the mean weight of the heart is above that of the 
healthy heart (p. 67), but slightly below that of the general hospital population 
heart (p. 65). The weight of the spleen is somewhat above that of the healthy 
spleen (p. 67), and only about equal to that of the general hospital population spleen 
(p. 65). The absolute variabilities of both heart and spleen in pneumonia are far 
lower than the values in the general hospital population, and only slightly higher 
than their values in the case of healthy organs. The same remark applies to 
relative variabilities, which are in the case of this disease somewhat higher than 
the healthy values, but considerably below those of the general hospital population. 
We must therefore conclude that pneumonia does not influence in a marked degree 
the average values or the variabilities of either heart or spleen weights. As it 
