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APPARATUS 1. 1. Carbon-Zinc Cell. Fig. 1. If you have some rubber bands you can quickly make a cell out of rods of zinc and carbon. The rods are kept apart by putting a band, B, around each end of both rods. The bare wires are pinched under the upper bands. The whole is then bound together by means of the bands, A, and placed in a tumbler of fluid, as given in . This method does not make first-class connections between the wire and rods. ()... more...

In an inventive tour de force that seldom, if ever, has been equalled for its brilliance and far-reaching consequences, James Watt radically altered the steam engine not only by adding a separate condenser but by creating a whole new family of linkages. His approach was largely empirical, as we use the word today. This study suggests that, despite the glamor of today's sophisticated methods of calculation, a highly developed intuitive sense,... more...

Since its first publication "Agriculture for Beginners" has found a welcome in thousands of schools and homes. Naturally many suggestions as to changes, additions, and other improvements have reached its authors. Naturally, too, the authors have busied themselves in devising methods to add to the effectiveness of the book. Some additions have been made almost every year since the book was published. To embody all these changes and helpful... more...

CHAPTER I Introduction to Plants Our object in reading and studying this book is to find out some facts that will help those of us who are thinking of going into farming and gardening as a business or recreation to start right, and will also help those of us that are already in the business to make our farms and gardens more productive. In order to make the book of greatest value to you, I would urge you not only to read and study it, but... more...

FACTS AND OBSERVATIONS ON THE SALMON. In the following observations I intend to offer some remarks on the various migratory fish of the genus Salmo; and then some facts and opinions which tend to show the importance of some change in the laws which are now in force regarding them. We have first the Salmon; which, in the Ribble, varies in weight from five to thirty pounds. We never see the fish here before May, and then very rarely; a few come... more...


Advantages of Common-Battery Operation. The advantages of the common-battery system of operation, alluded to in Chapter XIII, may be briefly summarized here. The main gain in the common-battery system of supply is the simplification of the subscribers' instruments, doing away with the local batteries and the magneto generators, and the concentration of all these many sources of current into one single source at the central office. A considerable... more...

Introduction The art and science of agriculture embrace most intentional human efforts to control biological activity so as to produce plants and animals of the sort wanted, when wanted. Rubber plantations, cattle ranches, vegetable gardens, dairy farms, tree farms, and a host of similar enterprises all represent human efforts to compel nature to serve man. Those who undertake agriculture have had, from time immemorial, a variety of names, not... more...

PREFACE "Let posterity know, and knowing be astonished, that on the fifteenth day of September, 1784, Vincent Lunardi of Lucca, in Tuscany, the first aerial traveller in Britain, mounting from the Artillery Ground in London, and traversing the regions of the air for two hours and fifteen minutes, on this spot revisited the earth. In this rude monument for ages be recorded this wondrous enterprise successfully achieved by the powers of chemistry... more...

FOREWORD We are not tied to a desk or to a bench; we stay there only because we think we are tied. In Montana I had a horse, which was hobbled every night to keep him from wandering; that is, straps joined by a short chain were put around his forefeet, so that he could only hop. The hobbles were taken off in the morning, but he would still hop until he saw his mate trotting off. This book is intended to show how any one can trot off if he... more...

CHAPTER I ESSENTIALS OF SUCCESS Columella, the much traveled Spanish-Roman writer of the first century A. D., said that for successful farming three things are essential: knowledge, capital and love for the calling. This statement is just as true today as it was when written 1900 years ago by this early writer on European agriculture. Every man who loves the calling and has an ambition to become a successful farmer should understand that no... more...