Excerpt from The Catholic World, Vol. 57: A Monthly Magazine of General Literature and Science; April to September, 1893 The efficiency of motors has increased most wonderfully. In the first rude essays at human flight the only available source of power was that of the human muscle, which meant at least a thousand pounds per horse-power, if continued for any consider able time. Giffard's steam-engine and boiler taken together weighed, according to his own report of September, 1852, one hundred and ten pounds per horse-power. Some years later Mr. Stringfellow constructed a small model which is said to have weighed only thirteen pounds per horse-power. This, though never thoroughly tested, was for a long time referred to as a triumph of mechanical Skill. While both scientific and um scientific writers were debating the possibility of ever construct ing a large motor of like efl'iciency, Mr. Maxim went resolutely to work and, at one step, reduced the weight to less than ten pounds per horse-power. This achievement certainly astonished the scientific and engineering world. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.