He had made great progress in the industry of the men who tear off lead, who plunder the roofs and despoil the gutters by the process called double pickings.

• 他最先学习的技艺是针对屋顶的，他大大发展了拔除铅皮的技能，运用所谓“切牛胃”的方法来破坏屋顶结构和溜槽。