380 



REPORT — 1903. 



In all cases the length of bearing surface on the sides of the screw 

 must not be reduced below that given by the standard form of screw. 

 In Schedule I. the effective diameter is a mean of the outside and core 



Fig. 1. 



diameters, and the dimensions 

 cations) are equal to each other. 

 Schedule II. 



figured Ti To in fig. 1 (called trun- 

 The values of Tj T2 are tabulated in 



