In the location of new railways and the improvement of lines already in operation, it is now well recognized that large economies can be effected by the careful study of train resistance due to grades and alignment, distributing this resistance so as to secure a minimum cost of operation with the means available for construction. While engaged in such studies some years ago, the attention of the writer... more...

PREFACE A collection of about 2000 questions asked by children forms the foundation on which this book is built. Rather than decide what it is that children ought to know, or what knowledge could best be fitted into some educational theory, an attempt was made to find out what children want to know. The obvious way to discover this was to let them ask questions. The questions collected were asked by... more...

The Child and the Curriculum Profound differences in theory are never gratuitous or invented. They grow out of conflicting elements in a genuine problem—a problem which is genuine just because the elements, taken as they stand, are conflicting. Any significant problem involves conditions that for the moment contradict each other. Solution comes only by getting away from the meaning of terms that is... more...

I Remember Cheese Cheese market day in a town in the north of Holland. All the cheese-fanciers are out, thumping the cannon-ball Edams and the millstone Goudas with their bare red knuckles, plugging in with a hollow steel tool for samples. In Holland the business of judging a crumb of cheese has been taken with great seriousness for centuries. The abracadabra is comparable to that of the wine-taster or... more...

CHAPTER I."Filled with the face of heaven, which from afarComes down upon the waters; all its hues,From the rich sunset to the rising star,Their magical variety diffuse:And now they change: a paler shadow strewsIts mantle o'er the mountains; parting dayDies like the dolphin, whom each pang imbuesWith a new color as it gasps away,The last still loveliest, till--'tis gone--and all is... more...

In issuing this volume of my Mathematical Puzzles, of which some have appeared in periodicals and others are given here for the first time, I must acknowledge the encouragement that I have received from many unknown correspondents, at home and abroad, who have expressed a desire to have the problems in a collected form, with some of the solutions given at greater length than is possible in magazines... more...

INTRODUCTION. In an article, entitled "Then and Now," published in the December number, 1890, of "The Arena," its author, a distinguished Unitarian D.D. of Boston, Mass., says. "Astronomy has shattered the fallacies of Astrology; and people have found out that the stars are minding their own business instead of meddling with theirs." Now, while it is true that modern Astronomy... more...

The Chemistry of Food and Nutrition By A.W. Duncan, F.C.S.   We may define a food to be any substance which will repair the functional waste of the body, increase its growth, or maintain the heat, muscular, and nervous energy. In its most comprehensive sense, the oxygen of the air is a food; as although it is admitted by the lungs, it passes into the blood, and there re-acts upon the other food which... more...

AN A D D R E S S Gentlemen, S Nature hath been so very Indulgent to ye, as to stock your Gardens with Trees of the largest Growth, for which Reason ye are caress'd, whilst Men of less Parts, tho' in some Things more deserving, are laugh'd at, and excluded all Company. As all Infants, especially of the Female Sex, are much delighted with Fruit, so as their Years and other Appetites... more...

THIS exhibition has been arranged with a desire to meet the convenience of those who are interested in manifestations of the arts of different countries over which Islam held sway at one time or other in the past. An effort has been made to show under one roof representative examples of works produced at different epochs and stages of the civilizations referred to, so that they may be seen, and perhaps... more...