Excerpt from Welding: A Practical Treatise on the Applications of Electric, Gas, and Thermit Welding to Manufacturing and Repair Work Welding, an Ancient Art. The art of joining metals is one of the oldest known to man. Even since the first cave dweller or half-monkey man hammered his first piece of iron or copper between two stones, the development of the art has gone forward, and will probably continue to go forward as long as men use metals. The welding of iron is apparently as old as the produc tion of that metal by man, for there is, in a temple yard of the ancient city of Delhi, India, an iron pillar nearly two thousand years old, which shows unmistakable evidences of having been welded. The shaft projects 22 feet above the surface of the ground, extends over 40 feet into the earth, and is about 16 inches in diameter. It was apparently welded into one piece from blooms weighing about 70 pounds each; the joints are as nearly perfect as if they had been made with our most modern equip ment, and yet they must have been forged by hand. Conditions for Successful Welding. Strictly speaking, weld ing is the uniting, or joining, of two pieces of metal by hammer ing them together while they are hot enough to be plastic, and the application of the term is thereby almost limited to work done in a blacksmith shop. Broadly speaking, however, any process by which two pieces of metal are joined by causing cohesion of the molecules of the pieces is called welding. The best modern methods of welding are those in which cohesion is effected by means of high temperatures produced with gas or electricity. Many metals which cannot be welded by hammering may be welded by the new processes, which include brazing and soldering. 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.