Show several reasons A advanced for keystone nickname the nickname Keys keystone tono used for or pennsylvania says the PhU philadelphia adelphis inquirer li is of doubtful origin but the theory given most credence Is that it was so BO named because ot of its central position among tha states at the time of the adoption of the federal constitution other theories s advanced are that the name Is derived from the arch of it bridge across the rock creek between georgetown and washington D V C which contained 13 stones named tor for the 13 original states the keystone was marked with the letters Jetters pa on display at the american philosophical society which was glyen to this country by fran france c a in 1784 1781 represents thi the 13 american americ 1 n states inthe form of a sto rah with pennsylvania in the keystone position another suggestion Is that Pennsylvania was the last colony to vote foi or the declaration ot of independence pen dence dince completing thus the A arch ach ch ol of liberty |