This appeared in Strange Suspense Stories Issue #19 published in 1954. It must win the award for the most irresponsible advertisement ever!
"Fly Like A Bird With Wings Made From The Original Sketch of Leonardo Da Vinci's Flying Wings.
Now any adventure loving boy can build Da Vinci's flying wings with just ordinary carpenter's tools. OFFERED FOR THE FIRST TIME People said it couldn't be done but Leonardo went right ahead and built the wings and then carted them to a nearby hill and took off.
What happened is excitingly told in THE BIRDMAN, The Story of Leonardo Da Vinci. See the actual original sketch, Leonardo used to build his flying wings with just ordinary tools.
EXTRA SPECIAL TREAT
Also in THE BIRDMAN: The diagram of the parachute which Leonardo invented. Yes, you too can make a parachute out of cloth and string by just following Leonardo's drawing.
EXCITING - THRILLING
Whether you build the flying wings, the parachute or other of Leonardo's inventions, one thing is sure, you will enjoy the exciting and thrilling story, THE BIRDMAN, which is illustrated in color with the kind of pictures you like to look at. You don't have to buy THE BIRDMAN which is only 98c because you can send for it for a 10-day trial and if you don't get a real kick out of THE BIRDMAN the cost will be nothing."