In some images , Hu employed a blind embossing technique ( known as " embossed designs " ( gonghua , 拱花 ) or " embossed blocks " ( gongban , 拱板 ) , using an uninked , imprinted block to stamp designs onto paper . He used this to create white relief effects for clouds and for highlights on water or plants . This was a relatively new process , having been invented by Hu 's contemporary Wu Faxiang , who was also a Nanjing @-@ based publisher . Wu had used this technique for the first time in his book Wisteria Studio Letter Paper ( Luoxuan Biangu Jianpu , 蘿軒變古箋譜 ) , published in 1626 . Both Hu and Wu used embossing to create decorative writing papers , the sale of which provided a sideline income for the Ten Bamboo Studio .