one which has been actually laid out and measured.

This net is a part

of the work done by the United States Geodetic Survey, and is that portion of it which covers the whole State of New Jersey. It is copied from reports kindly furnished by Mr. G. H. Cook, State Geologist of New Jersey. It includes all the stations in New Jersey, and a few in

the surrounding States, in all forty-seven stations. They are all firstclass stations. To show how slow geodetical triangulation has necessarily to be, it may be stated that in the small State of New Jersey alone this work has been going on for nearly thirteen years, and is now nearly completed, only a few stations remaining to be covered at the beginning of the year 1886.

I may here state also that a few of the historical facts I have given are taken from "Elements of Geodesy," by J. Howard Gore, B. S., just published.

The idea of connecting the various measurements in the different European states was later on improved upon, and for the purpose of obtaining good, reliable data, collected on a system of uniformity sufficiently numerous and covering a large area of territory, all the states of Continental Europe have combined in the interest of science. If each country did its work separately, and the data obtained in one could not be compared with others, the observations made would have only a local value, and, being limited in extent, could not have that scientific weight which it is necessary they should have. All European countries have felt the necessity of having thorough topographical surveys made, so as to possess good, detailed maps of their territory. This work being considered necessary for military purposes, its execution has been undertaken by the military authorities. The triangulation work necessary for this purpose could, with little addition, be extended so as to connect the geodetical nets of the various countries and form a complete system of nets extending over the whole continent. An agreement was entered into, by the various states into which Europe is divided, that the geodetic data which were being collected and the observations that were being made should become common property, and that all the observations being made on a standard of uniformity agreed upon by all parties concerned, they should be used in common. for the purpose of furthering the scientific problem and obtaining a series of nets, by means of which the exact distance between any two points on the European Continent could be easily calculated.

The common work-that is, the direction of the whole as an international undertaking, each country doing its own share within its own. borders-has been confided to an international commission specially founded for the purpose, and which is known as the Commission Internationale pour la Mesure du Degré en Europe. All the states are represented in this commission, the representatives being mostly the heads of the geodetical department of each country, and some of the best-known astronomers. The best specialists of Europe, who have devoted their life to this branch of studies, belong to this commission.

The international agreement makes it possible to have uninterrupted chains of triangles across the whole continent, from north to south, and from east to west. It is, however, not necessary that the

nets should extend over the whole area of each country. Neither the topographical necessities nor the scientific requirements make such a complete geodetical survey indispensable. Those countries possessing a comparatively larger territory would find a complete triangulation too costly and too slow. Each country has therefore laid its nets as it thought best. The Atlantic countries, France and Spain, have laid a series of parallel nets from north to south, and another from east to west, crossing each other almost at right angles. Supposing each of these nets to be drawn on the map, but instead of the various triangles a thick black line to be laid down as a sort of central line of each separate net, the whole systems would have the appearance of square grates or pigeon-holes. Germany and Austria have not observed the same rule; their lines are less regular in form, although just as convenient for the purpose. Italy and the smaller states have found it necessary to cover their whole territory, on account of their irregular geographical form, or their smallness. Sweden and Norway have run several nets, and also Russia; but the vast area to be covered leaves a thorough and systematic triangulation of the whole country out of the question.

The control which observations extending over such a vast area permit is very great. The possibilities of its being extended over a still wider field are only limited by political difficulties and by the great cost necessary for its execution in half-civilized countries. The result of the work undertaken by the International Commission can not fail to be of the highest scientific value, and the standing of the men who compose it is a guarantee that the greatest efficiency and thoroughness characterize the work done.

Of the calculations necessary, and which follow the field-work, the least said the better. To an outsider, one who is incapable of comprehending the scientific purpose of the same, they look very much like time wasted and which could have been better employed. It will suffice to say that all calculations are made twice and independently of each other. Each set of calculators do their work independently of the other, and only compare the final result. Months and months elapse before a partial result is reached, and before other and more complicated calculations can be begun. But the battle-field is one worthy of man; he has arrayed himself against figures, and, although slowly, he conquers them with the help of formulas, equations, and logarithms, all children of his fertile brain. The scientific result is obtained with scientific means. From beginning to end, geodetical triangulation is purely scientific; nothing is left to chance, and, although it can not by any means be mathematically precise, it comes as near the point of complete correctness as it is possible for any human thing to be.

THE

SULLY'S HAND-BOOK OF PSYCHOLOGY.*

BY CARVETH READ.

HE "Outlines of Psychology" was written, as the title-page showed, "with special reference to the theory of education." Sometimes in the midst of the text, but chiefly at the end of each chapter, abundant remarks and reflections were introduced, showing the bearing of the principles of mental science upon the training of faculty and character in the young. The work has been (as it deserved to be) very acceptable to the public-especially to studentsand it would be a great mistake to suppose that the present "Handbook" is intended to, or possibly can, supersede it. But it has been felt that the "Outlines," in spite of its modest title, is too long and detailed, and sometimes perhaps too abstruse and difficult, for many parents and teachers, who would gladly see their task in the light of science, but either have not much time to spare, or else lack the special training that is requisite for the more intricate questions of psychology. For them, accordingly, the present smaller volume has been produced.

The "Hand-book " begins with a discussion of the scope of education and of its relation to psychology. After this preliminary chapter the book is based upon and follows generally the course of the “Outlines," giving a succinct but luminous view of the best scientific doctrine with regard to the senses, perception, the higher intellectual powers, the emotions, and volition. But the applications of the science to the problems of education are no longer, as in the larger work, separated from the exposition of the science itself by any difference of type or arrangement. Doctrine and precept are fused into a continuous whole, which, assisted by an openly printed page and an effective style, becomes, I must say, extremely readable, considering the nature of the subject. Upon each branch of the subject enough is said concerning the principles of psychology to serve the ordinary purposes of the educator; and everything is said so simply that no one, however unaccustomed to such inquiries, can fail to follow and understand it. There is no attempt to enter into subtile disquisitions or vexed controversies. The bog-fires of metaphysic, hardly seen to glimmer on the borders of the demesne, can tempt no wayfarer to go astray. Every sentence is subordinated to the single end of clearing up the problem how best to train the minds and characters of the young. And the inferences drawn step by step as the book advances, and the suggestions made upon this most important of all subjects, are an admirable example of the application of science to life. Who can help wishing

*The Teacher's Hand-Book of Psychology. On the Basis of the "Outlines of Psychology." New York: D. Appleton & Co. 1886.

to have been born later, and to share the more enlightened instruction. that awaits the next generation ?

If I were to take exception to anything in the scientific aspect of this book, it would be chiefly to the treatment of conception, judgment, and reasoning, which seems to me too much under the influence of ordinary logic. But even here what seems to me questionable lies more in the expression than in the thought; and there is, after all, in this part of the exposition some advantage in availing one's self of the terms and distinctions of logic; since many readers will partly understand them to begin with, and will thereby be more readily familiarized with the abstruser ideas of psychology. Still, this advantage may be bought too dear. In the practical aspect of the book, I am inclined to say that it lays too much stress upon the importance of authority in moral training. But probably few of those for whom the book is intended will think the author's doctrine of discipline overstrict. His treatment of the emotions and sentiments in relation to education, a particularly difficult and important part of the work, seems to me especially good.

It is a striking fact, the sudden turning of so many first-rate minds. to the subject of education; and a great revolution in scholastic affairs,, however gradual, will certainly result from it. No subject ought to be so universally interesting. If none seem so tedious to us, it may be because our own education was so bad; or that we have reflected so little about it that new suggestions find in our minds no soil to strike root in; or that the complexity and practical difficulties of it paralyze our faculties in any case, the more reason for spurring ourselves to the study. There is no subject more beset with popular errors, none in which science is more useful, explanatory, and suggestive. Not only every professional educator, but every father and mother (amateur educators!), ought to have some acquaintance with psychology. However absurd this seems, I defend it on the ground that nothing else enables one to interpret the faint and fragmentary recollections of having been one's self a child: without which how can other children be known, and, if unknown, how trained? At school I often used to wonder whether the masters had ever been to school, they knew so little of what we boys were thinking, feeling, and about to do. I have heard an educated woman say of her baby, squalling of course at six months old, "I believe he knows he's doing wrong." Heautomorphism, in default of science, is ever the first resource of explanation; i. e., we judge of others by ourselves. Discipline without knowledge, and therefore without sympathy, an outside wooden machinery, hampering and crushing, is the same in schools, in homes, and in prisons.

Science is certainly useful; yet it may be perverted by an ingenious mind. It has been urged that, according to the theory of evolution, education must with each generation become less necessary: I suppose, because the amount of inherited faculty grows greater. But

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