JB,
That is the version I was able to get. Mine was from amazon and according to the description - has been at a high school library since 1976. I just hope it is intact and all pages present.
Well sir, seeing that we are about the same age, it appears that I am 45 years behind you in reading this.
I too had a real like for the 1851 but the Richards conversion was always a desire to own, never did though. CAS for me was mainly a 1873 clone.