In practice, the operation would be somewhat as follows, generally speaking: The lens would first be focussed on the animate scene to be photographed. 弗兰克·刘易斯·戴尔.爱迪生的生平和发明.
The story of the part the new invention had played quickly spread abroad, and added to the intense public interest now focussed on it. 鲁伯特·萨金特·荷兰.历史性发明.