The revolver pictured at the bottom has the "creeping" loading lever. It first appeared on the 1860 Army (.44 cal). Next was the 1861 Navy (.36 cal), and the final appearance was the 1862 Police (.36 cal.).
I really liked the 1860 because the grips are big enough for me to get my hand onto. But for ease of use, the 1862 with the 4 1/2" barrel is the best balanced.
John (Bigsmoke)