DETEEMINATION OF SIZE OF HEART BY X-RAYS 



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young and the older age groups show relatively larger hearts 

 than the others. The Vierordt figures show relatively smaller 

 hearts than the* Miiller groups but larger than the Thoma 

 groups. In this connection it should be noted that like Thoma, 

 Vierordt takes a theoretical weight for a given age and divides 

 this by the average heart weight of hearts of individuals of 

 that age. Vierordt bases his estimates of body weight on data 



