to cap his evening , laurence read to him a little ; when their patience for going over the by-now-familiar material had faded , he put the book down , and temeraire said , `` i have been thinking , laurence , of the valley : perhaps we might take some of this red stone out of the desert with us , as we return , and use it in building a pavilion : would it not make an interesting pattern , with the yellow stone there ? ''