The wealthiest Europeans built great mansions in the late 19th century, some of which survive. "Casa de Fierro" (Spanish for the Iron House) is said to have been designed by Gustave Eiffel, designer of the Eiffel Tower in Paris, but evidence supporting this claim is scant. After an Englishman smuggled rubber seeds out of the area to establish competing rubber plantations in British colonies in southeast Asia and Africa, the Peruvian boom came to an end. In addition, a 1913 investigative report by Roger Casement, British consul-general to Peru, revealed the abuses of indigenous workers in the Amazon Basin by the Peruvian Amazon Company (PAC), owned by businessman Julio César Arana. Its several British board members and numerous stockholders in London were pressured to force changes in operations of the company. Many British divested themselves of this company in an effort to force changes. Arana returned to Peru, where he remained in charge of the PAC. Asian rubber was soon produced at lower cost and undercut that of South America, and rubber declined in importance in Peru.