"The Curlytops At Happy House or The Mystery of The Chinese Vase" was written by Howard R. Garis and published in 1931. This is number 13 of the Curlytops Series which was written during the popularity of the Nancy Drew and Bobbsy Twins series. The book has gray cloth covers with a maroon embossed title and illustration. There is a turquoise crayon (?) marking on the boy's elbow. The end papers are illustrated and there is an inscription in the designated place. The pages are mildly yellowed and the cover has some light soiling. There is foxing on the first 7 pages. The binding is tight and the pages are otherwise clean.