N.P. Ames of Springfield, MA, manufactured approx. 4,250 Jenks ""Mule Ear"" carbines for the U.S. Navy circa 1843 to 1846. This single shot, percussion, breech loading 54 caliber carbine is unusual in that it has a side hammer, thus the term ""mule ear"". The 24.5"" round barrel of this carbine has an excellent bore with bright, strong rifling. The barrel retains approx. 97% of its original brown finish with just a little wear toward the muzzle. It is marked at the breech W JENKS over USN over RC (inspector's initials) over P over 1845. The lock plate and breech lever show much of their original case hardened colors. The lock plate is marked N.P. AMES over SPRINGFIELD over MASS and W JENKS at the tail. The brass bands, butt plate, and trigger guard have an even age patina. The sling ring is mounted on the rear of the trigger guard. The stock is fine with an old gouge at the front of the lock, a few other issue dents and dings, no cracks or chips, and two inspector's cartouches. The action functions correctly. The mule ear Jenks were the only side hammer arms adopted by any U.S. military service.