thus obtained is utilized in a separate cylinder, and useful work obtained from it. After a considerable amount of trial and experiment on the part of Professor E. Josse, of Berlin, SO, was selected as the most suitable material with which to work. Liquid SO, is therefore used to condense the exhaust steam, and being vaporized in the process is capable of doing useful work, either in a supplementary cylinder to the steam engine, or in a separate engine.

It is hoped that the foregoing remarks will be taken in the spirit in which they are written, namely, of friendly criticism and praise-an attempt to point out the faults and good points in all cases. That the engine builders of all countries have succeeded in developing in their respective branches and countries such magnificent machines is a fact of which all engineers without national distinction should be proud,

Vol. 7-19

PROGRESS IN ENGINEERING.

BY ROBERT HEYWOOD FERNALD.

[Robert Heywood Fernald, engineer; born Crono, Me., Dec. 19, 1871; educated at University of Maine, Massachusetts Institute of Technology, Case School of Applied Science, and Columbia university; is professor of mechanical engineering in the Washington university at St. Louis, Mo.; has written many monographs chiefly dealing with the result of his own scientific investigations.]

The past century has been a period of special significance in the development of technical education, and is properly regarded as the era of its most important advancement. Reviewing the history of this period, we find ourselves, even at its beginning, a long way from the original source of technical education, which is, in fact, prehistoric. A brief sketch of the earliest known results of this type of education is of value as revealing the foundation of its more recent accomplishments.

The Bible states that Tubal-Cain, the inventor of the art of forging metals, was "an instructor of every artificer in brass and iron"-and this nearly 4,000 years B.C. The building of the great cities of the ancients required a knowledge of materials and methods of construction which seem marvelous to-day, and manufacturing and other industries must have formed a necessary part of the evidently active life of ancient communities. The cutting of the great monoliths from the quarries of Syene, together with the inscriptions wrought upon their faces; the raising of these huge masses of stone to form the pyramids; the building of great tombs in these structures, as well as the excavating into the mountains of the region for a like purpose, and the application of the mechanic arts in ways more refined and delicate, but nevertheless enduring, lead directly to the conclusion that the foundation of technical training and a knowledge of technical principles are as old as civilization; and in tracing the history of engineering education in any country