electrolytic corrosion of lead-thallium alloys

1
674 CURRENT TOPICS. [J. F. I. advantages when large quantities of scrap are to be remelted, in minimizing the accumulation of sulphur and carbon, and thus reducing the amount of virgin metal required for the charge. H. L. The Age of the Earth.-This question was the subject of a formal discussion at the recent meeting of the British Associa- tion for the Advancement of Science. Lord Rayleigh made the opening remarks, relriewing the methods that have been pro- posed. Lord Kelvin’s calculations based on a limit of the sun’s heat and the internal heat of the earth have been upset by the discovery of radioactivity. Lord Kelvin gave but a limited dura- tion to the period in which the earth was cool enough to support the life that is now on it, a result which was not acceptable to many geologists and paleontologists, who believed that the e\:i- dence of the fossil remains indicated a much longer period. Darwin termed Kelvin’s result “an odious spectre.” The changes undergone by uranium have been recently made the basis of calculation, and especially the accumulation of lead in uranium-containing minerals. The upshot of the calculations at hand is a moderate multiple of one billion years as the time during which the earth was suitable for living beings, and data from physics or astronomy afford no definite presumption against this vie\\r. Rayleigh waives any discussion of the biologic and geologic data. J. W. Gregory says that the best-known geologic estimates require to be multiplied ten or twenty-fold in order to agree with the physical estimates. A. S. Eddington suggests that Lord Kelvin’s time-scale should be lengthened five-huntlretl-foltl, at least during the stage of evolution. Gregory makes a curious mistake in saying that the claim that geologic time covered only a few score million years was regarded by geologists as of little more use than the “ seven days of the Pentateuch.” The creation, however, is given in the Pentateuch as having taken only six days. H. L. Electrolytic Corrosion of Lead-Thallium Alloys.-Fink and l<ldritlge in a communication to the recent (fortieth) meeting of the American Electrochemical Society report experiments undertaken with a view to minimize the loss of metal in anodes used in procedures of copper precipitation in Chile. It was found that an alloy of 70 per cent. lead, 20 per cent. tin and IO per cent. thallium lost only 1.2 pounds per IOO pounds of copper precipi- tated. It was also found that, in general, alloys with high melting points are more resistant to corrosion. The liquid subjected to electrolysis in the operations studied was a solution of copper sulphate containing nitric and hydrochloric acids. The low cor- rosion is due to a strongly adherent film formed on the anode. 1-I. L.

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Page 1: Electrolytic corrosion of lead-thallium alloys

674 CURRENT TOPICS. [J. F. I.

advantages when large quantities of scrap are to be remelted, in minimizing the accumulation of sulphur and carbon, and thus reducing the amount of virgin metal required for the charge.

H. L.

The Age of the Earth.-This question was the subject of a formal discussion at the recent meeting of the British Associa- tion for the Advancement of Science. Lord Rayleigh made the opening remarks, relriewing the methods that have been pro- posed. Lord Kelvin’s calculations based on a limit of the sun’s heat and the internal heat of the earth have been upset by the discovery of radioactivity. Lord Kelvin gave but a limited dura- tion to the period in which the earth was cool enough to support the life that is now on it, a result which was not acceptable to many geologists and paleontologists, who believed that the e\:i- dence of the fossil remains indicated a much longer period. Darwin termed Kelvin’s result “an odious spectre.”

The changes undergone by uranium have been recently made the basis of calculation, and especially the accumulation of lead in uranium-containing minerals. The upshot of the calculations at hand is a moderate multiple of one billion years as the time during which the earth was suitable for living beings, and data from physics or astronomy afford no definite presumption against this vie\\r. Rayleigh waives any discussion of the biologic and geologic data.

J. W. Gregory says that the best-known geologic estimates require to be multiplied ten or twenty-fold in order to agree with the physical estimates. A. S. Eddington suggests that Lord Kelvin’s time-scale should be lengthened five-huntlretl-foltl, at least during the stage of evolution. Gregory makes a curious mistake in saying that the claim that geologic time covered only a few score million years was regarded by geologists as of little more use than the “ seven days of the Pentateuch.” The creation, however, is given in the Pentateuch as having taken only six days.

H. L. Electrolytic Corrosion of Lead-Thallium Alloys.-Fink and

l<ldritlge in a communication to the recent (fortieth) meeting of the American Electrochemical Society report experiments undertaken with a view to minimize the loss of metal in anodes used in procedures of copper precipitation in Chile. It was found that an alloy of 70 per cent. lead, 20 per cent. tin and IO per cent. thallium lost only 1.2 pounds per IOO pounds of copper precipi- tated. It was also found that, in general, alloys with high melting points are more resistant to corrosion. The liquid subjected to electrolysis in the operations studied was a solution of copper sulphate containing nitric and hydrochloric acids. The low cor- rosion is due to a strongly adherent film formed on the anode.

1-I. L.