"Please be patient with me"
"So was the one the army used a #3, only chambered for the shorter .45 S&W cartridge"
Yes. It was a No. 3.
Bear with me, this is a little confusing...
The US Army actually used SEVERAL different No. 3s.
The first, the .44 American, was the first cartridge revolver adopted by the US Army in, IIRC, 1869.
It was chambered for the .44 Smith & Wesson, which after a few years became known as the .44 S&W American to differentiate it from the .44 Smith & Wesson cartridge.
The Army only took a few thousand of those revolvers as a stop gap measure while it and Colt were finalizing what would become the Model 1873 Peacemaker.
After adoption of the Peacemaker, the Army requested that S&W submit another series of revolvers for evaluation. These were, for all intents and purposes, identical to the .44 Americans, except that the Army wanted them chambered in .45 Long Colt, which had been adopted with the Model 1873 Colt.
S&W said "Nope, can't do it because it would require us to re-engineer our entire gun due to the length of the cartridge," but they submitted guns chambered for a shorter cartridge, the .45 S&W.
Around the same time, Col. George (? I think that's correct) Schofield, a Cavalry officer who was testing one of the revolvers in .45 S&W, approached the company with several changes that he contended would make the arm of MUCH better service to the Cavalry.
The primary change was to strengthen and relocate the latch, making it less likely to pop open inadvertently and also making it easier to open while on horseback.
Smith & Wesson saw the benefit of those changes and started producing those guns, which becamse the Schofield model revolver.
The Schofield model is STILL a Number 3 revolver, but it's a modified No. 3.
After the Army contracts fell through Smith & Wesson went BACK to the original latch design because it was cheaper to produce.
but with a different trigger guard?
No. The Schofield had the standard Number 3-style trigger guard.
The Russian model, though, had a modified trigger guard that was, to the best of my knowledge, produced ONLY on the guns contracted by Russia.
The Russian Model, though, is still a Number 3.
About 1876 or so the Russians also proposed a number of other changes to the basic model, including the shape of the grip.
S&W decided to adopt a modified grip on all Number 3s going forward, and generally these guns are known as New Model Number 3s.
What happened to, or what were the #1's and #2's?
How best to explain this...
Smith & Wesson used numbers to designate the basic size of the revolver's frame.
In the case of the Number 1, those were the original Smith & Wesson break open revolvers, chambered for a number of rimfire cartridges.
Only, with the Number 1, the hinge was on the TOP of the frame, not the bottom.
Right after the Civil War, S&W flipped that round and introduced the Number 1 and 1/2. It chambered most of the same cartridges, but the hinge was on the bottom of the frame.
The Number 2 revolver was the medium sized frame for centerfire cartridges like the .32 S&W and the .38 S&W.
The Number 3 was the full sized, or what we'd probably today call the Magnum, frame for the large-bore cartridges.