Technology & Engineering Books

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Introduction This report has been undertaken for a special reason. It is to explain to the taxpayer just why so many of his dollars are going into the American effort to explore space, and to indicate what he can expect in return which is of value to him. Such an explanation, even after 2 years of relatively high-geared activity in the space exploration field, appears to be warranted. There is still a... more...

INTRODUCTORY It was at Mons in the third week of the Great War. The grey-green German hordes had overwhelmed the greater part of Belgium and were sweeping down into France whose people and military establishment were all unprepared for attack from that quarter. For days the little British army of perhaps 100,000 men, that forlorn hope which the Germans scornfully called "contemptible," but... more...

INTRODUCTION Since the earliest communities of human beings first struggled for supremacy and protection, the principles of warfare have remained unchanged. New methods have been evolved and adopted with the progress of science, but no discovery, save perhaps that of gunpowder, has done so much in so short a time to revolutionize the conduct of war as aviation, the youngest, yet destined perhaps to be... 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... more...

The year 1913 marks the close of the first fifty years since Abraham Lincoln issued that famous edict known as the emancipation proclamation, by which physical freedom was vouchsafed to the slaves and the descendants of slaves in this country. And it would seem entirely fit and proper that those who were either directly or indirectly benefited by that proclamation should pause long enough at this... more...

CHAPTER I ACOUSTICS Telephony is the art of reproducing at a distant point, usually by the agency of electricity, sounds produced at a sending point. In this art the elements of two general divisions of physical science are concerned, sound and electricity. Sound is the effect of vibrations of matter upon the ear. The vibrations may be those of air or other matter. Various forms of matter transmit... more...

THE MEN BEHIND THE MACHINES I MACHINES. AS SEEN FROM A MEADOW It would be difficult to find anything in the encyclopedia that would justify the claim that we are about to make, or anything in the dictionary. Even a poem—which is supposed to prove anything with a little of nothing—could hardly be found to prove it; but in this beginning hour of the twentieth century there are not a few of us—for... more...

CHAPTER I INTRODUCTORY Fish culture of a certain kind dates from very early times, but its scientific development has only come about quite recently. Most people know that in our own country the monks had stew ponds, where they kept fish, principally carp, and also that the Romans kept fish in ponds. In the latter case we hear more often of the eel than of other fish. The breeding of trout and salmon,... more...

by: Anonymous
HOW NEWSPAPERS ARE MADE. We will suppose that it is a great newspaper, in a great city, printing daily 25,000, or more, copies. Here it is, with wide columns, with small, compact type, with very little space wasted in head lines, eight large pages of it, something like 100,000 words printed upon it, and sold for four cents—25,000 words for a cent. It is a great institution—a power greater than a... more...

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... more...