(Yes, it's made of soap. From Lester Gaba's On Soap Sculpture.) I first came upon the subject heading soap sculpture in the Library Catalog a couple of weeks ago, and I just had to investigate. And what I found more than confirmed my love of the serendipitous nature of research.
I learned-—in looking through a few books on the subject as well as articles in Proquest's Historical New York Newspapers database-—that soap sculpture as a fashionable hobby was launched by Proctor & Gamble as a means of promoting brand loyalty for Ivory soap. The man behind this campaign was Edward L. Bernays, who has been called the Father of Spin. Proctor & Gamble sponsored a series of competitive soap sculpture exhibitions in the twenties, and winners took home cash prizes. Within the first three years of the campaign's launch, prizes totaling $1,675 were given to winners among no fewer than four thousand entries (as reported in the New York Times, June 6, 1928).
On Soap Sculpture by Lester Gaba (1935) provides both a short introduction to the soap sculpture craze as well as a guide for the amateur artist interested in this medium. This "Cinderella of Sculpture" (yet another book on the subject by Gaba) was without doubt ephemeral, and this makes the specimens pictured in Gaba's book even more impressive for their ambitious and sometimes unbelievably complex details.
↑ (Also from Lester Gaba's On Soap Sculpture.)
If you want to try your hand at soap sculpture, Ivory Soap is still ready to help with tips for "pure fun" with its soap. And you can come in and read about it at the Library too.