The Marlin Model 24 was made from 1908 to 1917. It was one of Marlin's most popular models as it had all the refinements that Marlin was working on at the time. It was a take down action that was simple to operate and the newer style forearm attachment method that eliminated cracking the forearm like the earlier models.
Be advised that the Marlin Firearms Company has issued a service bulletin advising owners of these early exposed hammer shotguns not to shoot them. There are internal problems that can make the gun dangerous to shoot. EVERYTHING must be in complete working order in order for the gun to be safe to shoot, and then using light loads only. There have been instances where the breech bolt was released from the action upon firing. (think about where your head is when you shoot it) The gun is safe if it is inspected and any problems corrected. You can find instructions for safety checks and repairs at http://www.100megspop3.com/oldvalkyry/marlin.htm