Given such an inborn trait and adequate opportunity for its development and training, and there results rare creative powers. A successful designer of machinery must have that rare mental attribute and equipment. He must discipline those talents to do effective work by many years of training and have actual experience in mechanical pursuits before he can do his best work. He must be familiar with all of the essentials of machine building and able to apply the most up-to-date determinations to his designs. He must be an able and accurate mathematician in order to be able to calculate and determine the forces acting upon every member of his machine, and know the strength of materials so as to be able to make those parts of such forms and proportions as to insure that they will do the required work with a minimum of material and labor in completing same. must be a constant and faithful student of the current books and periodicals pertaining to his art to keep posted as to the new things constantly being brought out. In short, the capable modern designer of machinery is an extraordinary man in his mental equipment, and he deserves the honor of being called an engineer and given a high place among those whose work has contributed most toward providing that wonderful array of utilities, comforts and conveniences of modern times.

By special machines I would refer to those designed along radically new lines to displace others heretofore employed for the same purposes, or new ones designed for new purposes. I would not include modifications of existing machines by additions of parts readily conceived of by suggestions from parts of other machines, or the aggregation of parts of several machines to form a new special machine, for an experienced draftsman can accomplish such designing without much creative effort, as the problems involved are comparatively simple.

In the design of a new machine for a new purpose the real ability of the designer is put to its supreme test, particularly if the new machine be for use in a field with which he is not very familiar. Such conditions are those generally met with by the independent specialist in that line of work, and he must needs be a very versatile and capable man to succeed in that field.

Let us imagine that we occupy the position of such an in

dependent designer, and that we have been retained to design a new special machine to perform a considerable number of operations on a certain product. These operations have all heretofore been performed by hand labor, with the assistance of a few simple jigs and tools. Competition compels a reduction in the cost of the product, and the manager of the enterprise believes that a machine can be produced, within reasonable cost, which will dispense with considerable manual labor and at the same time insure more uniform results.

The manager has confidence in our ability to develop the desired machine. We are determined to prove that we are equal to the task, but we give him distinctly to understand at the outset that we may fail to achieve all that he hopes and believes to be possible, within the limit of time he can allow us for our part of the work in producing the machine. It is always best to make that matter plain at the outset to insure that we do not trip ourselves by promising the impossible, under limitations which prevent us from doing our best. Such preliminaries, and the matter of our compensation, having been reduced to a written contract we are ready to proceed with our work.

Our first step is to procure all possible information regarding the work which the new machine is to do, and to make a careful record of all such information and data. We will also note the source and consequent dependability of all such information, so that we may not be misled by our information. To get such information considerable time can often be profitably spent at the factory, making time studies and noting the sequence of operations which are now employed in machining the part.

We will next make a careful study of the operations to be performed. We will analyze these operations scientifically to determine how many of them require practically the same amount of elapsed time for their completion. We will carefully note all such findings for use in later studies and determinations. Our next step is to determine how many of the operations requiring the same time interval are so disposed about the piece as to admit of simultaneous operations, without making the machine too complicated to be practical.

With all of the foregoing preparatory work well checked up for errors we are ready to make our first real effort on this job,

from the creative standpoint. We have been charging our minds. with all of the data and facts we could gather and from them we are to evolve the desired machine. We must throw on the mental screen a series of pictures which we create to embody the general form and proportions which the machine may possibly have, and we must hold each of those mental pictures clearly in mind while we proceed to analyze them as to their adequacy to embody all of the essential elements in a practical manner. One after another the pictures evolved are found lacking and are put on the shelf for possible further consideration, in some features. Hour after hour, and day after day this concentrated mental effort in making and analyzing mental pictures must be continued, without making a line or notation of any kind. Time after time we almost conclude that the machine cannot be produced, yet we are not willing to give up defeated. Eventually a picture is evolved, generally a composite of several elements of previous ones, which appears to embody all of the essential requirements. We concentrate intently upon it, to fix it firmly in our mind and then proceed to make a hurried rough sketch of the general features of the conception. At last we have a real but crude picture which is tangible to others, and we can proceed. to prove up the merit of our conception.

From this first sketch we proceed to make our first study layout, in the form of an assembly drawing of a rough nature -making some effort to determine the size and location of parts approximately. Next we will proceed to develop the assemblies of the several work-holding jigs, and the tools required for each operation, showing the part to be worked on in its true form and position with respect to the jigs and tools at each station of the successive operations. From these group assemblies, accurately made to scale, we determine the spaces required for clearances to avoid interferences, the location of all main center lines, etc.

Our next step is to locate the main center lines accurately on a new assembly drawing, which we must make to scale, and with a sufficient number of views to enable all essential parts of the machine to be shown thereon. After the essential working parts are all carefully laid out on this drawing we proceed to evolve and lay out the driving trains for operating the several

jigs, clamping devices, tools, etc., all on this same drawing. We are now ready to develop a framework to connect up and support all of the other parts and we will lay that in to complete our first actual working assembly drawing of the new machine.

From this working assembly of the whole machine the detail drawings are made of each and every part-changes on the assembly drawing being made as the development of the detail proves same necessary or desirable. The detail drawings are checked over for errors and then a new assembly drawing is generally, but not always, made for the purpose of building the machine on paper, to further check up the dimensions of the parts as given on the detail drawings, to insure that all errors have been eliminated, so far as possible, before actual construction of the machine begins.

Having done our final checking of the detail drawings we will proceed to properly number and list every piece of the machine, from the main frame to the smallest pin or screw, so that all information, as to the intent of the designer, is clearly and fully disclosed by the drawings and the accompanying list of parts.

We are now ready to proceed with having blue prints made and getting the manufacture of the machine under way, with every reasonable assurance that it will go together and operate as intended.

BURRITT A. PARKS*

Industrial engineering is a broad title, covering a multitude of subjects, for under this general head may be included the entire design, construction and operation of an industrial plant. It is not the writer's desire to attempt covering too broad a field, but merely to try and point out some of the ills afflicting the average industrial power plant and the methods for their bet

terment.

The power plant (and when the writer uses the word he wishes to include such mechanical equipment as boilers, engines, generators, pumps, motors, power transmission equipment, heating and drying systems, etc.), is looked upon in far too many manufacturing plants as a necessary evil. So long as the "wheels go round" the plant is considered satisfactory. Efficiency and economy are unknown words, and yet where in the entire establishment is there any greater opportunity for effecting savings and cutting the costs than in the power plant?

The greatest hindrance to making improvements and working out economies is the ignorance of the average management concerning this department of the plant. Being unable to see or understand more than the barest principles themselves, they are loath to permit any expenditure of money except for the necessary supplies or repairs to keep the plant in operation. This same management will keep the costs to a fraction of a cent on the manufactured output from raw material through each operation to the finished product, employing, in many cases, high salaried experts in the different departments to increase the efficiency of production, and consequently lower the cost of manufacture. However, when it comes to the manufacture of power, one of the largest single items entering into the cost of the product, the management would turn this department of the plant over to a man whom they expect to pay from $15.00 to $20.00

The foregoing two papers were contributed to the program by the Committee on Industrial Engineering.