The effect upon the man making the observation of knowing that his data, even though at the time they may seem unimportant, can be used for the deduction of vital laws, is plain.  He naturally feels that he is a part of a permanent scheme, and is ready and willing to put his best activity into the work.  The benefits accruing from this fact have been so well recognized in making United States surveys and charts, that the practice has been to have the name of the man in charge of the work printed on them.

ANYONE INTERESTED MAY BECOME AN OBSERVER.—­A review of the mental equipment needed by a measurer, or observer, will show that much may be done toward training oneself for such a position by practice.  Much pleasure as well as profit can be obtained by acquiring the habit of observation, both in the regular working and in the non-working hours.  Vocational Guidance Bureaus should see that this habit of observation is cultivated, not only for the aesthetic pleasure which it gives, but also for its permanent usefulness.

UNBIASED OBSERVATION NECESSARY.—­In order to take observations properly, the investigator should be absolutely impartial, unprejudiced, and unbiased by any preconceived notions.  Otherwise, he will be likely to think that a certain thing ought to happen.  Or he may have a keen desire to obtain a certain result to conform to a pet theory.  In other words, the observer must be of a very stable disposition.  He must not be carried away by his observations.

The elimination of any charting by the man who makes the observations, or at least its postponement until all observations are made, will tend to decrease the dangers of unconscious effect of what he considers the probable curve of the observations should be.

As has been well said, watching the curve to be charted before all of the data have been obtained develops a distinct theory in the mind of the investigator and is apt to “bend the curve” or, at least, to develop a feeling that if any new, or special, data do not agree with the tendency of the curve—­so much the worse for the reputation of the data for reliability.

OBSERVED WORKER SHOULD REALIZE THE PURPOSE OF THE MEASUREMENT.—­The observed worker should be made to realize the purpose and importance of the measurement.  The observing should always be done with his full knowledge and hearty cooeperation.  He will attain much improvement by intelligent cooeperation with the observer, and may, in turn, be able to be promoted to observing if he is interested enough to study and prepare himself after hours.

WORKER SHOULD NEVER BE OBSERVED SURREPTITIOUSLY.—­No worker should ever be observed, timed and studied surreptitiously.  In the first place, if the worker does not know that he is being observed, he cannot cooeperate with the observer to see that the methods observed are methods of least waste.  Therefore the motion study and time study records that result will not be fundamental standards in any case and will probably be worthless.