Ernest Rutherford, a talented young researcher at the Cavendish Laboratory at Cambridge, came to Canada in 1898 to become Professor of Physics at McGill University. He was drawn by the opportunity to work at the newly-opened world-class Macdonald Physics Laboratory. His research was in the new field of radioactivity, and his successes were arguably the first indication of the potential for pure scientific research in Canada. In 1908 he was awarded the Nobel Prize in Chemistry for the research he undertook at McGill, concerning the chemistry of radioactive substances.

At McGill, Rutherford studied the nature of the rays emitted by radioactive material, like radium and thorium. He devised ingenious methods to quantify radiation, and to characterize the invisible alpha (positively charged and hard to divert) and beta (negatively charged and easier to divert) rays.
As well as the expected alpha and beta rays, Rutherford observed a third kind of radiation from the element thorium. Rutherford, with his graduate student Harriet Brooks, undertook investigations that would support his hypothesis (with Frederick Soddy) that radioactivity is a process of transmutation of el Read More

Ernest Rutherford, a talented young researcher at the Cavendish Laboratory at Cambridge, came to Canada in 1898 to become Professor of Physics at McGill University. He was drawn by the opportunity to work at the newly-opened world-class Macdonald Physics Laboratory. His research was in the new field of radioactivity, and his successes were arguably the first indication of the potential for pure scientific research in Canada. In 1908 he was awarded the Nobel Prize in Chemistry for the research he undertook at McGill, concerning the chemistry of radioactive substances.

At McGill, Rutherford studied the nature of the rays emitted by radioactive material, like radium and thorium. He devised ingenious methods to quantify radiation, and to characterize the invisible alpha (positively charged and hard to divert) and beta (negatively charged and easier to divert) rays.
As well as the expected alpha and beta rays, Rutherford observed a third kind of radiation from the element thorium. Rutherford, with his graduate student Harriet Brooks, undertook investigations that would support his hypothesis (with Frederick Soddy) that radioactivity is a process of transmutation of elements. This shook the fundamental assumption that the elements represented the most basic form of matter.


© 2001, CHIN. All Rights Reserved.

Using a differential air calorimeter, Rutherford measured the heat given off from a sample of radium. The radiation heated the air in the right-hand flask, and displaced the xylene in the connecting tube. This change was measured by the current in the wire in the left-hand flask. Rutherford concluded that there was an enormous amount of energy latent in radium atoms. One historian has remarked that "It is no exaggeration to state that the innocent apparatus depicted by the two flasks … marks the beginning of the atomic age!" The instruments Rutherford used are noteworthy for their simplicity and their "home-made" quality. Rutherford designed the instruments himself, and they were constructed in the physics department’s machine-shop. It was the practice to return instruments to the machine shop so that the parts could be reused, but a colleague of Rutherford’s had the foresight to see that Rutherford’s apparatus were put aside. Today several pieces are preserved at the Rutherford Museum at McGill.
Using a differential air calorimeter, Rutherford measured the heat given off from a sample of radium. The radiation heated the air in the right-hand flask, and displaced the xylene in the connecting tube. This change was measured by the current in the wire in the left-hand flask. Rutherford concluded that there was an enormous amount of energy latent in radium atoms. One historian has remarked that "It is no exaggeration to state that the innocent apparatus depicted by the two flasks … marks the beginning of the atomic age!" The instruments Rutherford used are noteworthy for their simplicity and their "home-made" quality. Rutherford designed the instruments himself, and they were constructed in the physics department’s machine-shop. It was the practice to return instruments to the machine shop so that the parts could be reused, but a colleague of Rutherford’s had the foresight to see that Rutherford’s apparatus were put aside. Today several pieces are preserved at the Rutherford Museum at McGill.

© 2001, CHIN. All Rights Reserved.

DifferentialAirCalorimeter

Differential air calorimeter ca.1903 Used to estimate the energy emitted from a sample of radium.

Made by Ernest Rutherford, McGill University, Montreal
c. 1903
© 2001, CHIN. All Rights Reserved.


Diagram

Diagram of the differential air calorimeter

Courtesy of Dr. Montague Cohen, Rutherford Museum, McGill University.

© 2001, CHIN. All Rights Reserved.


Learning Objectives

The learner will:
  • Identify and appreciate the way history and culture shape a society’s science and technology
  • Describe scientific and technological developments, past and present, and appreciate their impact on individuals and societies
  • Describe how Canadians have contributed to science and technology on the global stage
  • Understand how technology and science interact

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