Popular Science Monthly/Volume 79/October 1911/The Progress of Science
LANGLEY MEMOIR ON MECHANICAL FLIGHT
In the development of mechanical flight the United States has taken an honorable place both in theory and in practise. The work of Langley, Chanute and the Wright brothers can not be paralleled by any other nation. While in many directions we have done more than our share in mechanical invention, it has often happened that we have depended on Great Britain, France and Germany for scientific principles. But Langley was an eminent physicist and Chanute a leading engineer. It is interesting to know how far their achievements in aeronautics were based on mathematics and physical research and how far on empirical trials. The Langley "Memoir on Mechanical Flight," just published by the Smithsonian Institution, gives full details in regard to the work done by Langley and under his direction. The first part of the volume was in the main written by him in 1897; the second part, dealing with further experiments with the small models and with the large aerodrome, has been written by Mr. Charles M. Manly, who became assistant in charge of the experiments in 1898.
In 1891 Langley announced as the result of experiments carried on through previous years that machines could be constructed which would give such a velocity to inclined surfaces that bodies indefinitely heavier than the air could be sustained upon it and moved through it at a great speed. As a result of experiment and theory it was proved that one-horse power
would propel and sustain in horizontal flight at a velocity of about forty miles an hour a little over 200 pounds. Langley's experiments were in the main made with a whirling-table which forces the model to move in horizontal flight and at a fixed angle. In 1887, however, he began experiments with free-flying models at the Allegheny Observatory, following Pinaud in using twisted rubber as motive power. Some forty models were made, but while, as Pinaud had shown, a small toy could be made to fly for a few seconds, the motive power was inadequate for a larger machine or a longer flight.
In 1891 Langley began the construction of a steam engine. Daimler had invented the internal-combustion engine in 1885, but its possibilities were not at first realized, and it was necessary to wait for the development of the automobile to demonstrate the remarkable combination of power and lightness in an engine which has made possible the contemporary aeroplane. After innumerable experiments a steam engine was constructed weighing about six pounds and of approximately one horse power. An aerodrome, chiefly of steel, weighing, apart from fuel and water, about twenty-four pounds, was launched on the Potomac River on May 6, 1896, and flew for over half a mile. It alighted with safety and performed a second flight on the same day. This was a performance of great historic interest. The paths of the aerodrome on May 6 and again on November 28 are here reproduced, as also an instantaneous photograph of the aerodrome in the air, which bears a remarkable resemblance to a contemporary picture.
In 1898 the board of ordnance and fortifications of the war department appropriated $50,000 for experiments with a man-carrying aerodrome. Langley was at first indisposed to complete the work which he had carried so far, believing that might be left to commercial enterprise. It was, however, undertaken with the assistance of Mr. Manly, who now describes the results in this memoir. The great difficulty, as before, was with the engine. A New York builder could not supply the gasoline engine for which he had contracted; no European builder thought it possible to supply a twelve-horse power engine weighing as little as 200 pounds. Mr. Manly at the end of the year 1901 had succeeded in constructing an engine of fifty-horse power, weighing about 200 pounds.
After long-continued experiments in adjusting the engine, the aerodrome was made ready for trial. The houseboat and launching gear caused innumerable difficulties but on October 7, 1903, at 12.20 p. m. the aerodrome, with Mr. Manly in control, was launched. The trial ended disastrously, owing to an accident by which a guy-post caught in the launching gear. Mr. Manly narrowly escaped drowning through entanglement in the wrecked machine. He showed great courage in again repeating the experiment under unfavorable conditions on December 8, when 1 again the launching gear was at fault, j and the aerodrome had no opportunity I to demonstrate its power of flight. Owing mainly to ridicule in the newspapers and the fear of its effect on
Congress the army board was unwilling to continue the work. In the meanwhile the Wright brothers had begun their experiments with flying machines and in the year of the trial of the Langley aerodrome accomplished their first flight with a motor. In 1905 they remained in the air for half an hour, but it was not until 1908 that they fully demonstrated the practicability of sustained flight. Langley died on February 27, 1906, at the beginning of the era of mechanical flight to which his researches had so largely contributed.
THE ADDRESS OF THE PRESIDENT OF THE BRITISH ASSOCIATION
Sir William Ramsay presided over the recent meeting of the British Association for the Advancement of Science at Portsmouth, and, like many of his predecessors in the chair, made an address that is of very general interest. He gave a clear account of ancient and modern views regarding the chemical elements, laying, as is natural, much stress on the new discoveries in which he himself has taken such a leading part. It is not possible to review the marvelous story of the recent developments of chemistry more concisely than is done in the address. It is of interest to note that fair William Ramsay maintains, though rather incidentally, the validity of his experiments from which he concluded that the metal copper is converted partially into lithium by the energy radiated from radium, and that thorium, zirconium, titanium and silicon are degraded into carbon. It will be remembered that Madame Curie was unable to confirm these results.
Sir William Ramsay passes from the disintegration of the atom to the question of the available supply of energy, especially for Great Britain. He tells us that each Greek freeman had five helots who did his bidding, saving him from manual labor and giving Athens its preeminence in literature and thought, but that people in Great Britain are still better off, each family having twenty helots represented by the consumption of fifty million tons of coal annually. It is this coal which has given England its great wealth and commercial supremacy. At the present rate of increase of consumption the supply will be exhausted within 175 years, and there appears to be nothing to take its place. The best advice that Sir William Ramsay can give is to use it economically. He, however, calls attention to the forestry systems of Germany and France, and the efforts in this country on behalf of conservation. He reminds us of the enormous quantity of energy stored up in radium and its constituents. If the energy of a ton of radium could be utilized in thirty years, instead of being evolved at its invariable slow rate of 1,760 years for half-disintegration, it would suffice to propel a ship of 15,000 tons, with engines of 15,000 horse power, at the rate of 15 knots an hour, for 30 years—practically the lifetime of the ship. To do this actually requires a million and a half tons of coal. We are told, however, that the production of radium will never surpass half an ounce a year. If, however, the elements which we have been used to regard as permanent are capable of changing with evolution of energy, and if some form of catalyzer could be discovered which would increase their slow rate of change, then a boundless supply of energy would be available for the human race. Sir William Ramsay says that it would be folly to consider seriously a possible supply of energy in an acceleration of the liberation of energy by atomic change; but he concludes the address with the remark that while radioactive substances are in all probability incapable of industrial application, apart from medicine, their study has shown us to what enormous advances in the concentration of energy it is permissible to look forward, with the hope of applying the knowledge thereby gained to the betterment of the human race.
THE DIRECTOR OF THE AMERICAN MUSEUM OF NATURAL HISTORY
Dr. Frederic A. Lucas, recently appointed director of the American Museum of Natural History, was born in Plymouth, Mass., in 1852. At the age of nineteen he entered Ward's Natural Science Establishment, a commercial museum for the preparation of natural history objects of all kinds. Here he acquired his first practical training in the preparation of natural history specimens, including the mounting of birds, mammals and other vertebrates, the preparation and mounting of skeletons and casts of fossils, and in time he became manager of the establishment. During his connection with the famous Rochester institution two of his colleagues were William T. Hornaday and Charles H. Townsend, and it is noteworthy that these three men who were working together thirty-one years ago should one after another have been called to direct the work of three of the most important institutions of the kind in this country if not in the world—the American Museum of Natural History, the New York Zoological Park and the Aquarium.
In March, 1882, Dr. Lucas was called to the United States National Museum as osteologist. He is to be credited with the assembling, preparation, mounting, classifying and labeling of the fine osteological hall of the National Museum. He was gradually promoted until in 1902 he was placed in charge of all the exhibits of the department of biology.
His admirable work in the National Museum and long experience in museum methods of preparation and exhibition, as well as his growing reputation as an investigator and writer, led to his selection as curator-in-chief of the Museum of the Brooklyn Institute of Arts and Sciences, where he had free play for his talents. Dr. Lucas's work in the Brooklyn Museum has been marked not only by great activity in the acquisition of specimens and collections but also by rare originality in the display of natural history objects, especially for the purpose of bringing out principles of zoology and classification in such a manner as to both attract and instruct all classes of visitors. He is practically the originator of the small but admirably arranged collection of vertebrates there, and no better nor more scientific installations of mammals are to be seen in any museum. The arrangement and labeling both from scientific and artistic standpoints are unique.
The especial purpose of the president and trustees of the American Museum of Natural History in the selection and appointment of Dr. Lucas as director is the advancement of the educational arrangement and exhibition of the vast collections which the museum has been acquiring from various parts of the world, especially during the past decade. In this field Dr. Lucas is recognized as the leading expert in this country. The trustees realize that the American Museum is very strong and well arranged in certain departments, while others lack sequence, and that either geographic, systematic or evolutionary sequence is necessary in order to give the collections their full educational value and effect.
SCIENTIFIC ITEMS
We regret to record the deaths of Dr. Francis A. March, professor emeritus of comparative philology and English literature at Lafayette College, of Dr. Thomas Dwight, professor of anatomy at Harvard University, and of Professor Franklin H. King, of Madison, Wis., known for his publications on agriculture.
Dr. E. A. Schäfer, professor of physiology at Edinburgh, has been elected president of the British Association, for the meeting to be held next year at Dundee, beginning on September 4. The meeting of 1913 will be held at Birmingham.
The annual Herter lectures will be delivered at the Johns Hopkins University on October 4, 5 and 6, by Professor Dr. Albrecht Kossel, of the University of Heidelberg, who was awarded the Nobel prize last year for his discoveries in medical chemistry.
Next year the American Geographical Society celebrates its jubilee, and in connection with this event a transcontinental excursion for the purpose of geographical study is planned, under the leadership of Professor W. M. Davis. The start from New York, by special train, will take place some time in August, and the excursion will conclude in October, its duration being six or seven weeks.
The South Australian Cabinet has decided to contribute £5,000 towards the cost of the Mawson Antarctic Expedition.