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Fig. 17.

wrought iron, steel, in turn, it will be found the textbook can be used much more effectively. Every student now has some experience to be appealed to, and he is gradually beginning to think and express himself in the technical terms of strength and elasticity. Tests are now made only to illustrate some new method of testing or some peculiar property. Thus, a complete tensile test is made on a finished specimen of steel, using an electric contact micrometer (Fig. 17). The broken

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ends of the steel or wrought iron specimens tested early in the course (Fig. 1), are retested to show the increase in strength due to rest after cold-working. A torsion test on steel is made with the Thurston Autographic machine (Fig. 18a), another test on a specimen from the same bar to show the exaltation of the elastic limit (Fig. 18b), and a third (Fig. 18c), to show that the elastic field is fairly constant, and that raising the elastic limit in one direction reduces it in the other.

DISCUSSION. OF PAPERS BY PROFESSORS HATT AND CHRISTENSEN.

PROFESSOR H. WADE HIBBARD: There is one criticism that it seems to me might be made, which criticism is directed at the methods which have been necessitated, perhaps, by the increase in the numbers of students taking laboratory courses of this sort.

I know we shall all remember the presidential address this evening, and I hope that we shall give particular remembrance to the thoughts that Dr. Dudley brought out with regard to real education. It seems to me that in the multiplicity of experiments, in the desire on the part of the experimental laboratories to get a large number of experiments, somewhat varied, in the blank forms and careful directions, that the principle of education-real education-may be somewhat obscured. This, according to our President, is not the pumping into the student's mind of a large amount of information, but the leading out from that student's mind, cultivating in that student's mind the ability to reason for himself, to be ingenious and to plan for himself, and scheme out his methods for making experiments himself. That, of course, means that not so many experiments can be performed by students, but what they do perform they get in a fashion that gives them education in experimental methods, and in the ways of thinking as testing engineers.

PROFESSOR W. F. M. Goss: The modern engineering laboratory contains apparatus of many different kinds. It has its steam engines, internal combustion engine, hydraulic apparatus and its machinery for testing materials. As I have followed the work of students along these different lines in a fairly busy laboratory, I have often been impressed with the fact that among them all none so well satisfy the requirements for the development of young men as the material testing. Work along this line lends itself most readily to the instruction of students. In the department of testing materials we are not liable to fall into those errors to which Professor Hibbard has referred. I am sure it is true that in all well-regulated laboratories the students in this department gather inspiration, their intellectual processes are quickened, they see purpose in the methods employed, and the working out of natural consequences in the results obtained. The whole tendency of the work is to arouse interest or enthusiasm.

I wish most heartily to commend the thorough manner in which the courses described have been systematized.

MR. WILLIAM METCALF: The thought that entered my mind just now in connection with the education of the engineer is the one prominently brought forth in the president's address, and that is, the importance of teaching a student to think. I think that is all that education is worth. I want to say a word here now that may seem proud, but I want to say a word for my alma mater. The one particular characteristic of that school throughout the whole course was, in my day, and I believe practically is now, that the student was taught only one thing at a time. He didn't have two hours a week at this, two hours a week at that, and two hours a week at another subject, and was not fed on mental hash all the way through so that at the end he would know everything; but every day and every week just one plain simple thing until he got through with that subject. The result was said to be tiresome by critics of the school. It was nothing of the kind. There was a little study in the morning, a little scientific recreation in the afternoon-the afternoon always given to some practical work, some laboratory work, drawing, etc., sufficient to teach the student at least the fundamentals of the tools he had to work with. He was always at one subject until he got through, and when he got through with it he generally knew it pretty well.

PROFESSOR MANSFIELD MERRIMAN: In listening to these very interesting discussions regarding the conduct of laboratory work, I have been impressed with the large amount of labor spent by instructors to systematize the work and prepare the necessary plans in order that the student may derive benefit from them. It may, indeed, be thought by some that in many instances the greater part of the mental work is done by the instructor and that there is not much left for the student. There are blanks for every stage of the work, and it is sometimes carried so far that there is a blank at one machine on pink paper and at another machine on brown paper.

On each piece of paper there are lines half-printed and the students regards it as an academic exercise to fill out the dotted portions. This is probably an extreme view to take of the matter. If the student should come into the laboratory with the oldfashioned, small engineer's field book with horizontal and vertical lines on opposite pages, and be required to take down notes from the experiments and bring in the next day his own report in the way he thinks it ought

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