Popular Science Monthly/Volume 71/September 1907/The Progress of Science

THE PROGRESS OF SCIENCE

HERMANN VON HELMHOLTZ

The nineteenth century is distinguished for the advance of science and the spread of democracy, and science is dominant as its applications have supplied the economic conditions that make democracy possible—general education, relative leisure and comparatively broad interests for a majority of the people. We may consequently regard it as probable that the greatest men of the century were its scientific leaders, and that they will ultimately be held in higher honor than the authors or artists, than the statesmen or soldiers. The doctrines of the conservation of energy and of organic evolution are the two greatest generalizations of modern science. Each has had its historical development both before and after, but is primarily associated with the one great name. We may believe that in the future everything connected with the life and work of Helmholtz or of Darwin will be of the deepest interest, and it is fortunate that the biographies that have been published are so adequate. "The Life and Letters of Charles Darwin," by his son. Dr. Francis Darwin, with the supplementary volumes of letters give a sympathetic and vital reflection of the noble and simple man and of his performance. The biography of Hermann von Helmholtz by Professor Leo Königsberger makes a more mechanical impression, but it gives a correct and useful account of the vast range of work accomplished by Helmholtz, and those facts of his private life that can be related objectively.

This biography published in 1902 and 190.3 has been abridged and translated into English by Lady Welby, with a preface by Lord Kelvin, and is now published by the Clarendon Press of Oxford. Of the eight portrait plates in the original, three are reproduced in the translation. In the two portraits by Lenbach the features are somewhat idealized. The bust by Hildebrand, made in 1891, is not given in the English volume, but more truly represents Helmholtz as he appeared during his visit to America toward the end of his life.

The paper on the conservation of energy, printed separately in 1847, after having been rejected by the leading German physical journal, may have been technically anticipated by Mayer and Joule, but it is the cornerstone of modern physical science. When this paper was published, Helmholtz was an army surgeon at Potsdam, his father, who was a teacher of classical languages, not being able to afford the cost of a university education. Thanks to von Humboldt, he was released from the army to become teacher of anatomy in the Berlin Academy of Arts. During his whole life, Helmholtz was deeply interested in the plastic arts, in music and in literature, thus demonstrating that there is no incompatibility between science and the fine arts. Of equal significance is his constant concern with philosophy.

Helmholtz became professor of physiology at Königsberg in 1849; he removed to Bonn in 1855 and to Heidelberg in 1858, remaining there for thirteen years. During this period he measured the velocity of the nervous impulse and prepared his great works on vision and on hearing, of which the ophthalmoscope was a by-product. Helmholtz's primary interests were always in mathematical physics, and he
Hermann Helmholtz at the Age of Twenty-seven. From a daguerreotype taken in 1848, a year after the publication of the paper on the conservation of energy.

consequently welcomed a call to the chair of physics in Berlin. Later he organized and became the first president of the "Reichsanstalt," a national laboratory of physics and technology. During these years, he made his great contributions to thermodynamics and electromagnetism, and with his pupils, Hertz, Lenard and others, gave to mathematical physics its dominant position among the sciences. All the while Helmholtz gave continually public addresses and popular lectures, and was engaged in commissions of all kinds. The range and quantity of his work are as remarkable as its epoch-making character.

LINNEAN CELEBRATIONS IN SWEDEN

At the beginning of the eighteenth century the military power of Sweden, so long a leading force in European politics, had been crushed, the people
Hermann von Helmholtz at the Age of Seventy. A bust made by Adolf Hildebrand in 1891.
had sunk into apathy broken only by intrigue and disorder, the nation was of no account. Then the son of a poor country priest, endowed merely with the divine love of nature and of knowledge, fought his way through school and university, and by constant observation and diligent study of subjects to which neither scholars nor men of the world then paid much attention, won a place among the great ones of the earth. Installed at Upsala, the youthful Linnæus first attracted thither students and men of science from all Europe, and then sent them through the whole world as gleaners of further knowledge and ambassadors of his country's new-found fame. Never since has Sweden relapsed from the high place thus won for her among nations in the wider world of scientific thought.

Medal in Honor of the Bicentenary of the Birth of Linnæus, struck by the Swedish Academy of Science. The first copy was awarded Sir Joseph Hooker, who celebrated his ninetieth birthday on June 30.

At the beginning of the twentieth century we have seen Sweden apparently losing prestige by the secession of Norway from the union; and, while we have admired the statesmanship that could accommodate itself with dignity to such a severance without the horrors of a brothers' war, we have seen a people mistrustful of its rulers, fearful of its neighbors, and bitter in its own heart. But in this celebration of the most eminent among her sons we may perceive at least one sign that Sweden is recognizing her true greatness. If she did not fully grasp it before, the homage of the world will have forced on her the truth of the Linnean motto—Famam extendere factis. Deeds, no longer of arms, but of honest labor in the ever-widening field of science. Sweden has received a blow; but the blow has aroused her. She stands up; she throws off the garment of slumber; she takes in her hand with renewed vigor the weapons of the future. Around the shrine of Linnæus all classes gathered together, and during those three bright days in a year of rain, as one paced the streets of Upsala and of Stockholm, beyond the celebration of the past, behind the feasts that welcomed spring, one beheld the renascence of a nation.

How appropriate were the words of Viktor Rydberg's beautiful Cantata as they sounded through the cathedral of Upsala during the impressive promotion of the doctors!

"And yet, if we have fallen down in doubt,
And by the way ye mourn and ponder gravely,
Lift up the banner! flame it out
Once more, and bear it through the desert bravely!
Care not, though ye perceive with piercing eye
A thousand suns from heaven's archway showering!
Care not, though 'neath the scythe of Time devouring,
Like golden seed the starry harvests lie!
All noble thoughts, all love that leads you on,
All beauteous dreams. Time never can see wasting;
These are a harvest garnered from his tasting,
'Tis to Eternity that they belong.
Advance Mankind! Be blithe, be of good cheer;
Since in your breasts ye bear the eternal here!"

What deep meaning too may one not see in the beautiful medal issued by the Royal Swedish Academy of Science! Here is the nature that the Swedes love so profoundly: the mountains in which are buried vast deposits of ore and fertilizing minerals, the woods and fields still unexhausted of their wealth, the waters with hidden incalculable energy. In their midst observes and ponders the naturalist who himself did so much to bring these natural treasures to the hands and homes of his countrymen, type of the thinkers who to-day are piercing further secrets and unlocking fresh stores. And there, in a clear sky, rises the sun.

RADIUM EMANATION AND THE TRANSMUTATION OF THE ELEMENTS

Sir William Ramsay has printed in Nature, for July 18, a letter, entitled "Radium Emanation," which is the basis of the alleged interviews which have been published in the newspapers. The author states that a full account of his researches will shortly be communicated to the Chemical Society. In his brief statement he calls attention to the fact that with Mr. Soddy he had shown in 1903 that the spontaneous change of the emanation from radium results in the formation of helium; this observation has been confirmed by others. Helium was once detected in the gases evolved continuously from a solution of thorium nitrate. When the emanation is in contact with and dissolved in water, the inert gas which is produced by its change consists mainly of neon; only a trace of helium could be detected.

Sir William now states that when a saturated solution of copper sulphate is substituted for water, no helium is produced; the main product is argon, possibly containing a trace of neon, for some of the stronger of its lines appeared to be present. The residue, after removal of the copper from this solution, showed the spectra of sodium and of calcium; the red lithium line was also observed, but was very faint. This last observation has been made four times, in two cases with copper sulphate, and in two with copper nitrate; all possible precautions were taken; and similar residues from lead nitrate and from water gave no indication of the presence of lithium; nor was lithium detected in a solution of copper nitrate, similarly treated in every respect except in its not having been in contact with emanation.

According to the author these results appear to indicate the following line of thought: From its inactivity it is probable that radium emanation belongs to the helium series of elements. During its spontaneous change, it parts with a relatively enormous amount of energy. The direction in which that energy is expended may be modified by circumstances. If the I emanation is alone, or in contact with hydrogen and oxygen gases, a portion is "decomposed" or "disintegrated" by the energy given off by the rest. The gaseous substance produced is in this case helium. If, however, the distribution of the energy is modified by the presence of water, that portion of the emanation which is "decomposed" yields neon; if in presence of copper sulphate, argon. Similarly the copper, acted upon by the emanation, is "degraded" to the first member of its group, namely, lithium; it is impossible to prove that sodium or potassium are formed, seeing that they are constituents of the glass vessel in which the solution is contained; but from analogy with the "decomposition-products" of the emanation, they may also be products of the "degradation" of copper.

SCIENTIFIC ITEMS.

We record with regret the deaths of Professor Angelo Heilprin, the eminent naturalist and explorer, professor of paleontology and geology in the Philadelphia Academy of Natural Sciences and lecturer in physical geography at Yale University; of Dr. William L. Ralph, curator of the Section of Bird's Eggs, in the U. S. National Museum; of Sir William Henry Broadbent, F.R.S., a leading London physician; of Dr. August Dupré, F.R.S., chemical adviser to the explosive department of the Home Office of the British government; and of Dr. Heinrich Kreutz, associate professor of astronomy at Kiel and editor of the Astronomische Nachrichten.

The tercentenary of the death of Ulisse Aldrovandi, the celebrated naturalist, was celebrated at Bologna, from June 11 to 13, in the presence of numerous delegates from foreign countries. A memorial tablet was unveiled, while a medal and several volumes compiled for the occasion were presented to the delegates.

The Norwegian Storting has voted the sum of 40,000 Kroner to Mr. Roald Amundsen in recognition of his services to science in traversing the northwest passage and relocating the magnetic North Pole.—Dr. Otto Zacharias, director of the Biological Station at Plon, and Dr. C. G. Schillings, the African traveler, have been given the title of professor by the German government.—Professor W. F. M. Goss, dean of the Schools of Engineering and director of the Engineering Laboratory of Purdue University, has accepted the position of dean of the College of Engineering in the University of Illinois.

The Royal Society of Medicine, composed by a union of medical societies in London, has received a royal charter. The society begins with a membership of 4,000 and an income of $40,000. Sir William Church has been elected the first president of the society.