Here is what I can make out. First gun is a 2nd Model, the second gun is a 4th Model, and the third is either a 4th or 5th Model, while the last is a 5th Model. Those with a pinned front sight were made before 1908 and the second 38 Safety has a pinned sight. Some very early 5th Models also have pinned sights, most likely from using left-over 4th Model barrels. One thing for sure is that there are no numbered models there, since model numbers did not come out until 1957-1958.
Where is the photo from?
I found the photo and it shows up on page 157 of Smith & Wesson Handguns, by Roper, but there is no caption that shows any Model number? Interesting though, but the third gun is called a 4th Model by Roper. It could be a 5th, but without the serial number, can't tell? One thing for sure is a mistake in ID was made on the second gun. It is actually a 4th Model and not a 3rd as Roper states. The 3rd has a push button latch.
I am still looking at the Roper picture and the second gun latch is not correct for a 3rd Model?? The frame of the 3rd Model did not reach the frame and a very pronounced push button latch sits at the rear of the top frame, but the image does not show either???