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JOHN C. KOCH 



moment of inoj'tin ol" tlie entire section is the sum of Ihe moment 

 of inertia of the compact hone and the effective moment of 

 inertia of the cancellated bone. 



5. Analysis of sections. The ccmiputations in complete detail 

 are given in tabular form, in table 4, for the effective moment of 

 inertia of section 8, which illustrates the methods employed 



Fig. 15 Transverse section 8 of normal femur. From the same subject as 

 figure 14. Enlarged figure with ruling of 2V inch squares, parallel to axis A-^, 

 to accompany table 4 which gives the complete calculations for the mechanical 

 properties of this section about axis A- A. See 'Analysis of Sections,' Part 

 III. Section 8 is shown natural size in Plate 1. 



throughout for the calculation of the moment of inertia. Figure 

 15 shows section 8 with the system of lines drawn at intervals 

 of 2V inch and parallel to the two principal axes of the section. 

 This figure forms the basis for the computations of table 4. 



In a similar manner the moments of inertia of the other sec- 

 tions have been calculated and reduced to terms of moment 

 of inertia of compact bone, which renders comparable the bend- 

 ing strengths of all the sections. 



