Background
Carl Barus was born on February 19, 1856, in Cincinnati, United States. His father, Carl Barus, Sr., was a musician and choirmaster; his mother, Sophia Moellmann, was a clergyman’s daughter.
1886
Carl Barus (front row, 2nd from right).
1900
Barus was awarded the Rumford Medal of America Academy Arts and Sciences for various researches in heat.
Columbia University’s School of Mines, New York City, New York, United States
Despite persistent financial difficulties, Barus attended Columbia University’s School of Mines from 1874 to 1876.
Julius Maximilian University of Würzburg, Würzburg, Bavaria, Germany
From 1876 to 1879 Barus studied at Wurzburg, where he took his Ph.D. under Friedrich Kohlrausch.
American Philosophical Society, 104 S. Fifth St. Philadelphia, Pennsylvania, United States
In 1892, Barus became a member of the American Philosophical Society.
Carl Barus was born on February 19, 1856, in Cincinnati, United States. His father, Carl Barus, Sr., was a musician and choirmaster; his mother, Sophia Moellmann, was a clergyman’s daughter.
Despite persistent financial difficulties, Barus attended Columbia University’s School of Mines from 1874 to 1876 and from 1876 to 1879 studied at Wurzburg, where he took his Ph.D. under Friedrich Kohlrausch.
After studying at Wurzburg, where he took his Ph.D., Barus worked for the United States Geological Survey (1880-1892), the United Slates Weather Bureau (1892-1893), and the Smithsonian Institution (1893-1894), where he assisted Samuel P. Langley with the development of the flying machine. Appointed to the Hazard professorship of physics at Brown University in 1895, he became dean of the graduate school in 1903 and taught until his retirement in 1926.
While at the Geological Survey, Barus worked in collaboration with the geologist Clarence King, an advocate of aiding the study of geological evolution with the laboratory analysis of rocks and minerals under high temperatures and pressures.
At the Weather Bureau, Barus’ research shifted to the condensation of water vapor on nuclei, but his departure interrupted his experiments. Resuming this work about 1900, he studied the effects of X rays and radioactivity on condensation in a fog chamber. The chamber, a cylinder made of wood impregnated with resin, was filled with moist air at atmospheric pressure and connected through a stopcock to another chamber at lower pressure. When the stopcock was opened, the air became supersaturated.
Barus concluded that ionization was relatively unimportant in condensation, but C. T. R. Wilson pointed out that his apparatus was unreliable. Wilson had published two authoritative papers in 1899 showing that ions produced by X rays and radioactivity were significant in condensation. He had used a chamber made almost wholly of glass; supersaturation was achieved by expansion at the sudden drop of a piston. Wilson sharply criticized Barus for ignoring the contaminating effect of the resin in his chamber and for failing to recognize that the stopcock method of expansion allowed condensation to occur before maximum supersaturation. In addition, Barus had failed to shield the chamber from the strong electric field of his X-ray apparatus.
Rutherford, who disliked the fragility of Wilson’s glass equipment, encouraged Barus to improve the fog chamber so as to explore the nature of X rays. But Barus soon dropped this work entirely, and by the 1920’s, despite continued publication, he had fallen into professional obscurity.
Quotations:
"The boon of an appropriate lemma is ideal generosity, and not even a mathematician can scorn its almost mathematical elegance."
"Out of 1,000 men who are called, one (probably the ratio is much smaller) is chosen to do glorious scientific work."
"A man may be a thoroughgoing soldier enough on land; but put him in the foot ropes of the flying jibboom in a storm, and he is apt to cut a most ludicrous figure. Shift a physicist's foothold of Cartesian differential coordinates, suspend him over an abyss of non-Euclidean space, and he will kick sturdily. Poor policy this, for a missionary!"
"In even greater measure is this true of the top. The top has been everybody's toy and must, therefore, at one time or another have piqued everybody's curiosity. Lagrange, Poinsot, Jacobi, not to mention other great names, have in turn paid their tribute; yet the top may be set spinning to-day, unhampered by a completed theory to account for its evolutions."
"I develop a method for the direct and expeditious comparison of the thermo-couple with the air thermometer. A comparison of the data... gives me a criterion of the accuracy with which the data in the region of high temperature are known. This indirect method... is not apparently as rigorous as their direct evaluation by means of the air thermometer; but the indirect method requires much smaller quantities of substance and may be conveniently extended to much higher temperatures. Taking all liabilities to error into consideration, its inferior accuracy is only apparent."
In 1892, Barus became a member of the American Philosophical Society, and at the same year he became the youngest of all members to National Academy of Sciences. He was also a member and the fourth president of the American Physical Society in 1905 and 1906.
Barus’s reputation was recognized by the many worldwide honors that came to him – he was a corresponding member of the British Association for the Advancement of Science, an honorary member of the Royal Institution of Great Britain, of the First International Congress of Radiology and Electricity at Brussels in 1905, and of the Physikalisch-Medizinische Sozietät at Erlangen.
Barus’s avocation was music, and he composed about fifty compositions “for home consumption,” among them a “March to Pembroke Hall,” and an “Ode to the Steam Shovel,” which was inspired by the daily noise outside his laboratory and was presented by him to President Faunce.
Barus married Annie Gertrude Howes on January 20, 1887. They had two children, Maxwell and Deborah.