Table of Contents
Transmutation of Hydrogen
(1) W. Ramsay, et al.
(1) William Ramsay, et al.
Dozens of scientific papers were published between 1905 and 1927 concerning the mysterious appearance of hydrogen, helium and neon in vacuum tubes. The matter has not been resolved.
The first such report, written by Clarence Skinner, was published in The Physical Review in July 1905:
"While making an experimental study of the cathode fall of various metals in helium it was observed that no matter how carefully the gas was purified the hydrogen radiation, tested spectroscopically, persistently appeared in the cathode glow..."
Skinner eventually located its source in the cathode. (26)
In 1912, Sir William Ramsay reported "The Presence of Helium in the Gas from the Interior of an X-Ray Tube", and J.J. Thomson published an article "On the Appearance of Helium and Neon in Vacuum Tubes" in 1913. Thomson was investigating a new gas called X3 (atomic weight 3: tritium), a polymerized form of hydrogen. He used the positive ray method to detect the helium and neon because it is more sensitive than spectral analysis and provides much more definite data. There was no apparent connection between the type of gas used to fill the tubes and the appearance of the new gases (X3 line 3 in H, N, He, O, and air; Ne line 20 in H, N, O, HCl, and air). Another line often appeared corresponding to atomic weight 10; it is probably due to neon with two charges of electricity, but brighter than expected. (22, 23, 29, 30)
The experimental apparatus was a large glass bulb fitted with aluminum electrodes; the discharge was produced by an induction coil. Thomson described it as follows:
"The positive rays for the analysis of the gases were produced in a vessel containing gases at a low pressure. I shall call this the testing vessel; the vessel in which the various processes for generating X3, were tried (the experimenting chamber) was sealed on to the testing vessel, but separated from it by a tap. Thus the pressure in the experimenting chamber was not restricted to being the same as that in the testing vessel, but might have the value which seemed most appropriate for any particular type of experiment. After these experiments were over, the tap was turned and some of the gas from the experimenting chamber let into the testing vessel; a photograph was then taken, and by comparing it with one taken before turning on the tap the new gases present in the experiment chamber could be detected."
Thomson finally determined that the gases were being occluded by the electrodes. He concluded:
"These gases are present in the metal independently of the bombardment, and are liberated by the action of the kathode rays.
"I would also like to direct attention to the analogy between the effects just described and an everyday experience with discharge tubes --- I mean the difficulty of getting these tubes free from hydrogen when the test is made by a sensitive method like that of the positive rays. Though you may heat the glass of the tube to melting point, may dry the gases by liquid air or cooled charcoal, and free the gases you let into the tube as carefully as you will from hydrogen, you will still get the hydrogen lines by the positive ray method, even when the bulb has been running several hours a day for nearly a year. The only exception is when oxygen is kept continuously running through the tube, and this, I think, is due, not to lack of liberation of hydrogen, but to the oxygen combining with the small quantity of hydrogen liberated, just as it combines with the mercury vapor and causes the disappearance of the mercury lines. I think this production of hydrogen in the tube is quite analogous to the production of X3, of helium, and of neon." (31)
Prof. N.J. Collie and H. Patterson conducted the early stages of their work independently and from different points of view. They began collaborating when they learned they were getting the same results. Patterson was interested in the pure physics of the electron, and had developed a hypothesis that "by doubling the electrical charge on hydrogen atoms, it might be possible to convert this into an a particle, and so into helium." He got neon instead. The experimenters took all due precautions against error, yet they repeatedly obtained traces of helium and neon. The tubes were surrounded by an exterior vessel which was evacuated, or contained neon or helium; the same results were obtained. In one such experiment, Prof. Collie tested the vacuum-evacuated exterior vessel and found helium with neon. Patterson replicated the experiment, and then repeated it with an oxygen atmosphere in the exterior tube. Neon was found therein. It appeared that neon was formed by a union of helium and oxygen. They also performed numerous blank experiments to exclude the possibility of contamination from various sources. (4, 9, 21)
R.J. Strutt and other workers found no helium in their experiments. (11, 15, 27)
In 1914, Collie reported his "Attempts to Produce the Rare Gases by Electric Discharge." Finely powdered, heated uranium was placed in a cathode discharge bombardment tube; the equipment was carefully purged in several ways. 1-2 hours of electrical treatment yielded traces of helium and neon in 11 experiments. Collie concluded:
"If the neon and helium found were due to an air leak, it is difficult to account for the disappearance of the argon, which should have been present to the extent of one thousand times as much as the neon and helium found. The amount of argon present, however, was too little to be measured, as it made no difference in the volume of neon and helium... The presence of the nitrogen is probably due to a nitride of uranium... That comparatively large amounts of neon and helium should come off from uranium by bombardment with the cathode rays, and not by heating, is a matter of interest; also that in one experiment a change of coil should affect the result is an observation that must if possible be repeated...
"That the presence of neon and helium in vacuum tubes, after the electric discharge has been passed, is due to an air leak seems most improbable. Where the gases come from has yet to be proved. They have been found by Sir J.J. Thomson, by Sir William Ramsay, by Mr. G. Winchester, and by the author [J. N. Collie], Mr. Hubert S. Patterson, and Mr. Irvine Masson... Whatever the source may be, it is only by further experiments that the question will be resolved..."
Collie, Patterson, and Masson described the electrical circuit, discharge tubes and testing apparatus, precautions and controls, bombardment experiments, results, and possible sources of the gases in the Proceedings of the Royal Society of London (1914).
"The coils gave 12-inch sparks with either a mercury or a hammer interrupter. The nature of the break has some influence on the result of the experiment; in the case of a mercury break, better results were obtained with a rectifier. The current in the secondary circuit averaged a few millamperes. The form of the discharge tubes varied from simple spectrum bulbs with disc electrodes to elaborate jacketed designs. The gases employed were generated by chemical and electrical methods and were tested for purity." (7)
The testing apparatus was either directly connected to the discharge tube, or the gases were transferred by means of an inverted siphon over mercury after being pumped from the reaction vessel. Hydrogen was removed by exploding it with oxygen in a burette or in the collection tube, which had platinum wires sealed in it. In some designs, the hydrogen was removed by copper oxide and phosphorus pentoxide. Oxygen and moisture were removed by cooled charcoal, liquid air, and Na-K alloy. The He and Ne were collected in a fine capillary tube with a fine platinum wire sealed through the top:
"It is found that the minimum quantity of neon detectable probably equals that contained in a few cubic millimeters of atmospheric air. If, owing to defective working, the neon actually was atmospheric, the accompanying argon would be very easily seen (as the ratio Ar:Ne in air is about 700:1) when the particular method used was such as might have eliminated nitrogen beforehand; in the apparatus depicted, nitrogen naturally made its presence at once evident if a very small part of a cubic millimeter of air was present... In many of the experiments, the total volume of gas used was so small that even if it had been all atmospheric air, it could not have accounted for the quantities of the neon, and still less for those of the helium, which were obtained... We wish to point out that a great many of our experiments have yielded negative results, for as yet unexplained reasons."
The electrodes were made of Pd, Cu, Pb, Tl, Li, Na, K, Al, and Mg. Some bombardment experiments were conducted with anti-cathodes of Pt, Tl, U, KF, KCl, KI, RbCl, Cs2CO3, CaO, and BeO. (14)
Besides the several precautions against air-leaks, Collie, et al., tested for nitrogen; The ratio of N2:Ne in air is about 80,000:1; therefore:
"If the Ne detected in an experiment came from air, the nitrogen accompanying it would be found in relatively overwhelming quantity...
"If atmospheric contamination occurs at any point after the run, nitrogen must infallibly be detected during the examination. If any contamination occurs before the run, it would likewise instantly be made manifest on the first passage of the discharge through the experimental tube. It is only when an infinitesimally slow leak goes on during the run that it is possible that no nitrogen could be seen at any time; and to provide against this contingency an additional control is necessary, namely the absence of argon from the gas... The argon test is in reality superfluously delicate as a control; nevertheless it was used.
"In all experiments where helium was the chief product, atmospheric contamination is ipso facto excluded... contamination seems to be thoroughly excluded in all the experiments."
Two hypotheses remained to explain the origin of the He and Ne: permeation through the walls of the tubes, and previous occlusion from them. Since positive results were obtained with electrodeless tubes, the electrodes can be eliminated as a source. In addition, when Al and other metals were melted in vacuo, no gases were occluded, but did so when the metals were bombarded; no He pre-existed in the metals. When Al was dissolved in KOH solution, no He or Ne was liberated. Melting the glass tubes in vacuo yielded no He or Ne. Two specimens of old glass (one Egyptian, approximately 1500 years old; another, Kien-lung Chinese) were examined; neither yielded He or Ne.
The authors closed their report with this note:
"We have endeavored to put the facts of the case as fully as possible, without reference to any preconceived theory. It is not our view that our experiments rigidly exclude all the possibilities which have been mentioned; but it is evident that the trend of the results is toward conclusions which, if they turn out to be true, would be of very obvious importance."
The issue then lay dormant for several years, but research was resumed after World War One. In 1926, Prof. Fritz Paneth and Dr. K. Peters determined that palladium had effected the transmutation of hydrogen to helium in their experiments. Paneth and Peters absorbed H in colloidal Pd (sponge, black, or palladinised charcoal) for 12 hours, after which time they detected the main spectral lines of He. No He production was observed with Pd preparations that had not absorbed hydrogen. Preparations of Pd stored at room temperature should therefore produce He; this was found to be the case. After the He had been removed, the sample was stored again, then examined; more helium was obtained. The experiment was repeated three times with the same results. (17-20)
The authors excluded all the possible sources of error in their experiments, such as the ingress of atmospheric He, absorption in glass or electrodes, preferential absorption of He by Pd, and the possibility of He being formed as a product of radioactive disintegration of Pd. No trace was detected of any energy liberated during the transformation, either as heat or radiation.
It would seem worthwhile and desirable to replicate these experiments with modern equipment and techniques.
1. Allison, S.K. & Harkins, William D.: J. American Chemistry Society 464: 814-824 (April 1924); "The Absence of Helium from the Gases left after the Passage of Electrical Discharges..."
2. Baly, E.C.: Ann. Reports on the Progress of Chemistry for 1914, Vol. II: 41-49 (1914); "Electric Discharge"; ibid., 1920, Vol. 17: 28-35 (1920); "Atomic Theory"
3. Baskerville, Charles: Popular Science Monthly 72 (2): 46-51 (Jan. 1908); "RecentTransmutations"
4. Collie, John N.:& Ramsay, William: Proceedings Royal Society London 59: 257-270, 356 (3 Feb. 1896);"On the Behavior of Argon & Helium..."
5. Collie, J.N. & Patterson, Hubert S.: Proc. Chemical Soc. 29 (410): 22, 23 (6 Feb. 1913); "The Presence of Ne in H..."; ibid., 29 (417): 217-221 (19 June 1913); Part II, "The Presence of Ne in H..."
6. Collie, J.N.: Proc. Royal Soc. London 90-A (621): 554-556; "Note on the Paper by T.R. Merton..."
7. Collie, J.N., et al.: Proc. Royal Soc. London 91-A (623): 30-45 (2 November 1914); "The Production of Neon & Helium by the Electrical Discharge"
8. Collie, J.N., & Patterson, H.: Chem. Soc. Trans. 103: 419 (1913)
9. Collie, J.N., & Patterson, H.: Chem. Soc. Proc. 29: 271 (1913)
10. Davis, Watson: Current History 25 (3): 393, 394 (Dec. 1926)
11. Egerton, A.C.G.: Proc. Royal Soc. London 91-A (627): 180-189 (1 March 1915); "The Analysis of Gases after Passage of Electric Discharge"
12. Harkins, William D. & Wilson, Ernest F.: The London, Edinburgh & Dublin Philosophical Magazine & Journal of Science 30 (179): 723-734 (Nov. 1915)
13. Hirshberg, L. K.: Harper's Weekly 57 (2938): 21 (12 April 1913); "Transmutation Explained Away"
14. Masson, Irvine: Proc. Chem. Soc. 29 (417): 233 (19 June 1913); "The Occurrence of Neon…”
15. Merton, Thomas R.: Proc. Royal Soc. London 90-A (621): 549-553 (1 August 1914); "Attempts to Produce the Rare Gases by Electric Discharge"
16. Nature 90 (2259): 653, 654 (13 Feb. 1913); "Origins of Helium & Neon"; ibid., 118 (2971): 526, 527 (9 Oct. 1926); "The Reported Conversion of Hydrogen into Helium"
17. Paneth, Fritz: Science 64 (1661): 409-417 (8 Oct. 1926); "Ancient & Modern Alchemy"
18. Paneth, F.: Nature 119 (3002): 706, 707 (14 May 1927); "The Transmutation of Hydrogen into Neon"
19. Paneth, F. & Peters, K.: Ber. d. DeutschenChem. Ges. 59: 2039 (1926)
20. Paneth, F.: Ber. d. Deutschen Chem. Ges. 60: 808 (1927)
21. Patterson, H.S.: Chemical Society Proceedings (1913), p. 233.
22. Ramsay, William: Nature 89 (2229): 502 (18 July 1912); "Experiments with Cathode Rays"
23. Ramsay, W.: Proc. Chem. Soc. 29 (410): 21, 22 (6 Feb. 1913)
24. Riding, R.W. & Baly, E.C.C: Proc. Royal Soc. London 109-A (749): 186-193 (1 Sept. 1925)
25. Scientific American Supplement 75 (1940): 150 (8 March 1913); "The Birth of the Atom"
26. Skinner, Clarence A.: Physical Review 21 (1): 1-15 (July 1905); "The Evolution of Hydrogen…”
27. Strutt, R.J.: Proc. Royal Soc. London 89-A (613): 499-506 (2 Feb. 1914); "Attempts to Observe the Production of Neon or Helium by Electric Discharge"
28. Sullivan, J.W.N.: Scientific American 108 (10): 226 (8 March 1913)
29. Thomson, J.J.: Nature 90 (2259): 645-647 (13 Feb. 1913); "On the Appearance of Helium & Neon in Vacuum Tubes"; Reprinted in Science 37 (949): 360-364 (7 March 1913) & Scientific American Supplement 75 (1940): 150 (8 March 1913)
30. Thomson, J.J.: Nature 91 (2774): 333-337 (29 May 1913); "Further Applications... of Positive Rays"
31. Thomson, J.J.: Proc. Royal Soc. London 101-A (711): 290-299 (1 July 1922)
32. Tolman, Richard C.: Journal American Chemical Society 44 (9): 1902-1908 (Sept. 1922); "Thermodynamic Treatment of the Possible Formation of Helium from Hydrogen"
33. Walden, Paul: Science 66 (1714): 407-417 (4 Nov. 1927); "What can the Modern Chemist Learn from the Old Alchemy?"
34. Winchester, George: Physical Review 3 (4): 287-294 (April 1914); "On the Continued Appearance of Gases in Vacuum Tubes"