portance for subsequent inferences may be forgotten by, the time the notes are written up.

The third component of an experiment is the mental scrutiny of the isolated facts which have been observed during the course of the experiment. The attitude of the scientific mind is not formed by the observation of isolated facts, but when the mind. works these facts over, ruminates upon them, then mental operations of real value in fostering this attitude, result.

This particular exercise, hard as it is to teach, is, nevertheless, the very backbone of good laboratory work. It is this exercise that gives laboratory work educational value. It is here that a student learns to think for himself, to investigate the facts and after weighing them, to judge for himself. Here he is freed from the text-book "ipse dixit."

From a practical standpoint no more useful training for after life can be given a student, for after all, we must admit, "the world and its problems are more like those of the laboratory than those of the library."

I confess that this is the crux of the laboratory course. If a teacher can handle this part of laboratory work with mastery, the educational value of it will be assured. The difficulty of handling this part satisfactorily may be the reason why this component of laboratory work is so often neglected altogether. However, as the attitude of the scientific mind is formed and developed by just this kind of exercise, teachers, knowing this, should bring their pupils to make strong, conscientious efforts to reach some kind of a conclusion unaided.

Thinking is a difficult matter to teach, no matter what method. is used to develop it, but I believe that laboratory method conducted along the lines outlined above, is one of the ways in which the great aim of education, the training of the mind to think clearly and logically on the practical affairs of life, is as fully realized as it should be.

So much then for the component parts of the experiment. The other constituent of iaboratory work is the notebook. Taken from the student's standpoint, the notebook is an effective means towards increasing and clinching the training given by laboratory experiment. For, as I conceive it, the laboratory notebook

should be a sample of original work, a record of personal observations and inferences of the student, in which he studies to make every statement exact, in which his accounts of observed phe nomena are correct, and in which the language used is precise.

The notebook is a progeny of the student's mind. For the student, it is perhaps, the first piece of real original work he has ever done. To the teacher it is a criterion of his mental caliber. Subsequently it will be called for to give evidence of his fitness for higher studies, and on its completeness and perfection depend in a great measure, the credits he will obtain, in other schools. To secure order and facilitate correction of the notebook, the contents should be arranged under the following topical headings: I, subject; 2, purpose of experiment; 3, apparatus and materials used; 4, observations; and 5, conclusions. I do not advocate tabulations, i. e., printed forms, these are mechanical both in form and effect on the student. It is a good plan to spend a class hour occasionally in having the notes read in class and asking criticisms on them. The inspection of the notebook is a tedious burden from the beginning of the year until the end, yet when one sees the clear ideas, the cogent expression, the sharpened powers of observation, and a growing facility to think clearly and logically, one realizes that the labor undergone is not without fruit.

I,

Finally it remains to treat of the principal obstacles that effectively hinder laboratory work from producing the cultural effects it is designed to foster. These obstacles are three: lack of coherence of laboratory experiments; 2, a want of laboratory class-plan; and 3, unsupervised laboratory work.

In regard to the first of these obstacles a moment's reflection will make it clear that a want of coherence of laboratory experiments will nullify the educational worth of the study because laboratory procedures have a weakness for resolving themselves into a series of isolated proceedings, mere mechanical acts without any interconnection with what has gone before or what is to follow.

To avoid such a condition in laboratory instruction, the teacher should arrange the class experiments into groups. The groups must be arranged in logical sequence, otherwise they will hardly

furnish the basis for that comparison, discrimination and the logical arrangement of facts which are the very pith and kernel of the laboratory course. The second obstacle, namely, a lack of class-plan, concerns the manner of preparing for teaching the class rather than the preparation of the matter.

The educational results of laboratory work will be effectively blocked unless the class work down to its minutest details is thoroughly thought out by the teacher before the actual class comes to the laboratory. Thinking-through-a-class is a partly imaginative, partly mental recasting of the class about to be taught. The purpose of the class is determined, its coherence with what has preceded is made clear, difficulties of technique and apparatus are foreseen, points that need emphasis are noted. It is a mental plan of the class where details, as far as possible, are foreseen and nothing is left to turn up by chance.

The third obstacle in the way of beneficial results from laboratory instruction, is unsupervised laboratory work. Laboratory periods are necessarily longer than other class periods. Hence there is danger that tedium of longer hours may be felt and as a consequence teachers will leave the classes alone for longer or shorter periods of time. Such a proceeding, where secondary and college classes are concerned, cannot be productive of the best results. As I said before, laboratory work has a knack of degenerating into mechanical procedures unless the teacher is on hand. all the while, with hints, questions and criticisms, to keep the mental faculties of students alert and active.

Where there is much unsupervised laboratory work students may readily imagine they are studying a science when in reality they are performing a number of disjointed processes of no cultural value whatsoever.

The tendency of laboratory work to become purely mechanical is always difficult to prevent, even when a teacher is on hand during the whole of the laboratory period. Laboratory work is designed to give a scientific knowledge of the matter in question, it is designed to foster a specific attitude of mind, and give a certain amount, too, of manual skill. Let the living teacher be absent or let the teacher be present in body but absent as regards questions, trenchant criticisms of manipulations or results, and a

student may as well be playing with blocks of wood as far as educational results are concerned.

In closing, I desire to draw your attention to one feature of laboratory work which should make it dear to all Catholic educators, and that is the personal influence that may be exerted by the teacher. It is here that laboratory study as a means of engendering moral power comes into sharp relief.

Catholic educators have always made much of this personal influence phase of education, and rightly so. They have uniformly made use of personal influence for the moral good of their students. Knowing, therefore, the close personal contact that exists between teacher and student in the laboratory, can moral influence be anywhere more naturally and unobtrusively exerted than at the laboratory table? I think not.

I know from my own experience that some of the deepest and most lasting impressions I have ever experienced resulted from laboratory study of chemistry and physics. In some vague, yet convincing way, these studies confirmed belief in the existence of a Supreme Intelligence, and realizing the manifold adjustments in nature for the good of man, I was made to feel that that Intelligence is good.

WHAT CATHOLICS HAVE DONE FOR ASTRONOMY

REV. WILLIAM F. RIGGE, S. J., F. R. A. S., DIRECTOR OF CREIGHTON UNIVERSITY OBSERVATORY, OMAHA, NEB.

If love of one's own is a virtue, if praise of our heroes is a noble passion, then we as Catholics have every reason to glory in the achievements of our co-religionists in all the sciences, and especially in astronomy, the noblest of them all. Catholic names occur in profusion in connection with this sublime study and in its every department. I do not mean that one will not find other names of high distinction, but ours are amongst the greatest in the world, and in some instances are the pioneers and acknowledged leaders.

As Catholic teachers, it is proper that we should know them and emphasize their achievements before our pupils. It behooves us to have at hand the information, founded, if possible, upon non-Catholic testimony, concerning their real worth. We ought to be able to refute glaring historical errors, and to vindicate our heroes from malign aspersions. It is the object of the present paper to contribute somewhat to this noble purpose.

The Calendar.

Passing over the oft-refuted fable that tries to connect Pope Calixtus III. with Halley's comet,' we find that the first and most prominent astronomical work done by Catholics is the reformation of the calendar. This is so exclusively the work of our own men that it was carried to its final and complete perfection before Protestantism was born. And it was so well done, thirty years before the invention of the telescope, and two centuries before even this became an instrument of precision, that, involving as it does an exact knowledge of the number of days and fractions thereof in the tropical year and in a lunation, with all the advances made during three centuries, we have as yet no adverse criticism to offer.

The Arabians.

It may be in place here to insert a word concerning the knowledge of astronomy we have heard so often ascribed to the Arabians during the so-called "Dark Ages." I give it on the authority of Newcomb, the greatest astronomer of his age, who died a year ago. He says that the Arabians "slavishly followed the system of Ptolemy, and made no attempts to penetrate the mystery of the celestial motions. They had little capacity for speculation, and throughout held the Greek theories in superstitious reverence." And J. W. Draper, a pronounced anti-Catholic, says: "So far as science is concerned nothing is owed to the Reformation."

Calixte III et la Comete de Halley, by J. Stein, S. J., Vatican Press. This is probably the most exhaustive historical investigation of the question that has ever appeared.

Encyclopedia Americana, title Astronomy.

"History of the Conflict between Science and Religion, Chap. VIII, p. 215.