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    Federal
 DIAMETER:  3.55 inches  | 
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| This specimen has six narrow ribs on the tapered cone. The brass Schenkl percussion fuze was patented by John P. Schenkl on October 15, 1861, patent #33,495. However, stamped on this specimen's fuze is "J.P. SCHENKL PAT. OCT. 16, 1861". An improved model was patented by John P. Schenkl on August 19, 1862, patent #36,236. | ||||