Radio-activity Quotes

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“An examination of the conductivity imparted to a gas by the X rays led to a clear view of the mechanism of the transport of electricity through gases by means of charged ions.”

“The rapid advance of our knowledge of radio-activity has been dependent on the information already gained by research into the electric properties of gases.”

“I have found the theory that the atoms of the radio-active bodies are undergoing spontaneous disintegration extremely serviceable not only in correlating the known phenomena but also in suggesting new lines of research.”

“The close of the old and the beginning of the new century have been marked by a very rapid increase of our knowledge of that most important but comparatively little known subject-the connection between electricity and matter.”

“A strongly radio-active body like radium is able to cause marked phosphorescence and fluorescence on some substances placed near it.”

“The value of any working theory depends upon the number of experimental facts it serves to correlate, and upon its power of suggesting new lines of work. In these respects the disintegration theory, whether or not it may ultimately be proved to be correct, has already been justified by its results.”

“There is no doubt that radium is a new element possessing remarkable physical properties. The detection and separation of this substance, existing in such minute proportions in pitchblende, has been due entirely to the characteristic property we are considering, and is the first notable triumph of the study of radio-activity.”

“A great impetus to the study of this subject was initially given by the experiments of Lenard on the cathode rays and by Rontgen's discovery of the X rays.”

“In this book the experimental facts of radio-activity and the connection between them are interpreted on the disintegration [of atoms] theory. Many of the phenomena observed can be investigated in a quantitative manner... the agreement of any theory with the facts, which it attempts to explain, must ultimately depend upon the results of accurate measurement.”

“On this theory we are witnessing in the radio-active bodies a veritable transformation of matter. This process of disintegration was investigated, not by direct chemical methods, but by means of the property possessed by the radio-active bodies of giving out specific types of radiation.”

“Mme Curie made a detailed examination by the electrical method of the great majority of known substances, including the very rare elements, to see if they possessed any activity. In cases when it was possible, several compounds of the elements were examined. With the exception of thorium and phosphorus, none of the other substances possessed an activity even of the order of 1/100 of uranium.”

“The term "radio-active" is now generally applied to a class of substances, such as uranium, thorium, radium, and their compounds, which possess the property of spontaneously emitting radiations capable of passing through plates of metal and other substances opaque to ordinary light.”

“Polonium was the first of the active substances obtained from pitchblende. It has been investigated in detail by its discoverer Mme Curie. ...This active substance... is so closely allied in chemical properties to bismuth that it has so far been found impossible to effect a complete separation. Partial separation of polonium can be made by successive fractionations.”

“Radium is extracted from pitchblende by the same process necessary to separate barium, to which it is very closely allied in chemical properties. ...The chloride of radium is less soluble than that of barium and can be separated from it by the method of fractional crystallization.”

“The ionization of the gas by phosphorus does not, however, seem to be due to a penetrating radiation like that found in the case of uranium, but rather to a chemical action taking place at its surface. The compounds of phosphorus do not show any activity, and in this respect differ from uranium and the other active bodies.”

“This ionization theory of gases has been shown to afford a satisfactory explanation not only of the passage of electricity through flames and vapors, but also of the complicated phenomena observed when a discharge of electricity passes through a vacuum tube.”

“Since the uranium is thus continuously radiating energy from itself, without any known source of excitation, the question arises whether any known agent is able to affect the rate of its emission. No alteration was observed when the body was exposed to ultra-violet light or to ultra-red light or to X rays. ..The intensity of the uranium radiation is not affected by a variation of temperature between 200 ºC and the temperature of liquid air.”

“ All the salts of radium are naturally phosphorescent. The phosphorescence of impure radium preparations is in some cases very marked. All the radium salts possess the property of causing rapid colorations of the glass vessel which contains them. For feebly active material the color is usually violet, for more active material a yellowish-brown and finally black.”

“The study of the radio-active substances and of the discharge of electricity through gases has supplied very strong experimental evidence in support of the fundamental ideas of the existing atomic theory. It has also indicated that the atom itself is not the smallest unit of matter but is a complicated structure made up of a number of smaller bodies.”