408 NOTE TO CHAP. XIV. . [APPENDIX, 



peratnre, the end momenta mysteriously disappear, and the 

 previously existing compression, due to load in upper flange at 

 crown and lower at ends, is exactly and entirely neutralized. 



Meanwhile it would seem that the St. Louis arch, as con- 

 structed, is far superior to the same arch hinged, more eco- 

 nomical of material and more rigid, and sanctioned alike by 

 theory and precedent. 



