4. How the rough draft is to be jotted down.
It must be here particularly remarked that our guns, carriages, &c., have no mathematically exact forms, and that therefore the number of measures to be taken must be often multiplied to have a true figure of the body.
A fair drawing from these measures in the above period is so much the less possible, as the number of objects is as much as possible multiplied. It is fully sufficient, however, for the purpose of this exercise, that the students learn to take complete and useful rough drafts.
On their entrance into the third cœtus, the complete drawings from these rough drafts take place.
In his selection of objects to be drawn, the teacher must, in having regard to variety, take care that the drawings by too great difficulty do not exceed the time and power of the students, nor by too great simplicity cease to be instructive.
Ordnance carriages, limbers, wagons, and the machines required in artillery, are the most suitable for choice, and are easiest obtainable in the arsenal.
The students must be divided into sub-sections, of at most three or four persons, and to each a separate task given.
The teacher is to be present at the drawings to see to their proper execution, and has delivered to him the notices and rough sketches to amend any errors that may be in them.
The relative section of the second edition of Burg’s “Drawing of Artillery Material” is to be taken as the basis for these exercises. In addition to them, the students receive guidance and suitable instruction in drawing artillery objects off-hand by the eye, without the use of instruments. The first two days are to be chosen for this, and the students by this use of off-hand drawing receive at the same time a useful preparation for the drawings subsequently required to be taken by the aid of instruments.
D. Exercises necessary in regard to Sieges—