This is a typical Nogent or rat-tail construction. The French have produced it until the sixties, in other countries the full tang with rivets was introduced much earlier.
Advantage of the Nogent: the handle is very light, very comfortable and can easily be replaced. Yes, it is likely to break. No big deal in those years. Ebony was cheap, labour as well.
The blade, fingerguard and tail are made of one piece of steel. A ferrule is added, often from alpaca Aka nickel-silver or German silver.
http://www.kitchenknifeforums.com/showthread.php/14035-my-first-nogent-handle
Your knife doesn't look too bad, but the profile has suffered from a lot of steeling. The tip has been rounded and moved far too high to be effective. Can easily be corrected but will cost a bit of the blade's length.