Now with further looked at it, it appears as if pressing down the raised lever at the rear of the hammer's spur, brings up a flat, probably blade-like peg that will extend the firing pin's nose, thus contact the firing pin - maybe. Not having the rifle in one's hand makes this guesswork.

With the lever raised as it is in the pictures, the peg sits below the hammer's nose thus cannot contact the firing pin which sits in a cut-tout in the rear of the rolling block.

If the lever was pressed down as it would be while bringing the hammer back to full cock, you would not see the black blade beneath the hammer's nose - third last picture is the best.

In the last picture, the hammer is seen fully down in the fired position. The nose of the hammer is quite short as seen in the 4th and 6th pictures from the top. The last picture shows the hammer's nose cannot contact the recessed firing pin, without help.