1918 Houghton Mifflin Company Ad - Why did the Kaiser and King Constantine

This is a 1918 ad for a Houghton Mifflin Company! The size of the ad is approximately 6x9inches. The caption for this ad is 'Why did the Kaiser and King Constantine Discuss this war at a secret conference six months before it started? In the Heart of German Intrigue by Demetra Vaka' The ad is in good overall condition, with some light wear. This vintage ad would look great framed and displayed! Add it to your collection today!