Yonin 4
Three Preliminary Assessments on Opening Gates (summary)
One
In the matter of opening doors. In a case where there is a lock on the gate, know well about that place and the details of the attached lock. Knowing the details will allow you to choose the method of breaking the lock. ...Therefore, once you have decided to break into a certain house, know its gate and appearance, after which you will be able to choose the appropriate tool for breaking the lock.

*This section of the Bansenshukai deals with methods of breaking various types of locks, and with specialized tools for breaking locks. Naturally, the types of locks, as well as the tools, are no longer in use. The information and the names provided in this text assume that the reader is familiar with them, thus there are no specific descriptions. Instead, the author provided the reader with some drawings. Yet, even the drawings are based on the assumption of the reader's familiarity with them. Consequently, it is impossible to provide a literal translation of terminology because it will make no sense. Without having in-depth knowledge of early-modern period locks such translation can not be done satisfactorily. Therefore, the current translation is rather a short summary of the opening paragraph.