The drawing courses of engineering curricula may be divided into two groups: (1) General courses, in which the principles and methods of representation are taught, together with such practice in drawing as will develop a satisfactory technique. (2) Technical courses, the aim of which is to assist the student to acquire technical knowledge or training, drawing being used primarily for the purpose of developing or testing a student's knowledge of the subject matter.
The general courses usually include an elementary course and a course in descriptive geometry. These courses deal with the fundamental principles and methods which have universal application in the advanced and technical courses. While the courses of the two groups may overlap, the general courses precede the courses of the technical group. There is no general agreement as to the order in which the subjects belonging to the general group should be given. Each of the following orders is in use:
1. A course in descriptive geometry followed by an elementary technical course.
2. An elementary course and a course in descriptive geometry given simultaneously.
3. An elementary course followed by a course in descriptive geometry.
The first plan is followed by a number of institutions which conclude, because of the general practice of offering courses in drawing in the secondary schools, that pupils entering college have a knowledge of the fundamentals ordinarily included in an elementary course. In other institutions it is held that the principles of projection can be taught to students of college age in a course of descriptive geometry without preliminary drill.
Where the second plan is used, the courses are so correlated that the instruction in the use of instruments given in an elementary course is applied in solving problems in descriptive geometry, while the principles of projection taught in descriptive geometry are applied in the making of working drawings. This plan is followed by several of the larger engineering colleges.
Under the third plan the principles of projection are taught through their applications in the form of working drawings. In this way the principles may be taught in more elementary form than is possible in any adequate treatment of descriptive geometry. The illustration of the principles in a concrete way makes it possible for those who find visualizing difficult, to develop that power before abstract principles of projection are taken up in the descriptive geometry. The skill of hand developed in the elementary course makes it possible to give entire attention to a study of the principles in the course in descriptive geometry. While excellent results are being obtained under each of the three plans, this plan is the one most generally adopted.
The order of courses in the technical drawing groups is determined by other considerations than those relating to drawing, such as prerequisites in mathematics, strength of materials, etc.
The elementary courses