It will be seen that certain lectures are much shorter than would be re quired to fill the entire periods allotted to them. This is done purposely so that there will be an opportunity for the instructor to make up for lost time, occasioned by inspections, etc., etc.; or an opportunity for quizzes, special lectures, and such other work as the instructor may desire. It will also be seen in the course for Motor Transport Company Mechanics that in places a four-hour period is devoted to certain lectures. This is done because the company mechanic must be a skilled workman and it is not enough for him to be informed on a subject; he must also be able to perform certain duties. The long lecture period permits reiteration, discussion and repeated demonstration on the part of the instructor, so that the student will get all details and be able to use his information. The instructor should use all his ability to put his ideas across in as many ways as possible to be sure that his class gets them thoroughly.