February 17, 1910] 



NA TURE 



461 



soft beta rays destroy all cells indiscriminately. Means 

 must accordingly be used to prevent the alpha and 

 soft beta rays from reaching the body. A filter con- 

 sisting of one millimetre thickness of lead is suitable. 

 .-Ks it is risky to send a patient away with a valuable 

 tube of radium crystals within his body, sealed glass 

 tubes of radium emanation have recently been used 

 {Lancet, December ii, 1909). They are enclosed in 

 lead tubing one millimetre in thickness. These tubes 

 of emanation do not differ from the crystals in the 

 rays thev emit or in their action ; there is, however, 

 one important difference ; the radio-active strength of 

 the emanation tube decavs according to an exponential 

 law in such a wav that the strength is reduced to one- 

 half at the end of about four days. Such tubes, of 

 about 10 milligramme strength, may be placed in 

 contact with a cancerous growth (say in the rectum) 

 and allowed to decay in situ. At the end of a fortnight 

 they may be removed, as being then too weak to be of 

 further use. ,_ , 



Other methods have been tried in a few cases ; 

 thus, dilute solutions of radium bromide have been 

 given by mouth, and water in which radium emana- 

 tion has been dissolved has been injected subcutane- 

 ously. 



Coming now to the results obtained, the accounts 

 are very confijcting. Undoubted relief has been 

 obtained in a considerable proportion of the cases ; 

 cancerous tumours have diminished in size, and have 

 disappeared altogether in some cases. But some of 

 the earlier cases reported as cured have since been 

 found to relapse ; in some cases the growth has re- 

 curred in the original situation, while in others can- 

 cerous deposits have formed in internal organs. It 

 seems fairly certain that in some cases cancerous 

 growths may be cured in their early stage by radium, 

 but it is not yet ju'itifiable to attempt this unless the 

 patient is so feeble (through heart disease or Bright's 

 disease, for instance) that the removal of the growth 

 by operation could not be undertaken. 



When the surgeon has declared a case inoperable, 

 radium (or Rontgen ray) treatment is used as a last 

 resource, and the attempt is usuallv a desperate one. 

 It is something, then, to be able to report the complete 

 disappearance of malignant growths in some of these 

 cases, even though the final result is not a cure. The 

 local treatment of cancerous growths does nothing to 

 prevent dissemination of the disease in the internal 

 organs, and Jt is with the idea of achieving this result 

 that attempts have been made to cause radium or its 

 emanation to circulate through the body. In doing so 

 it must be remembered that the alpha radiation is 

 giving out its full energv in the body ; and since this 

 radiation possesses about a hundred times as much 

 energy as the beta and gamma radiation together, it 

 is clear that for practical purposes we mav disregard 

 the effect of the gamma radiation in this connection. 

 Now, we started with the postulate that the alpha 

 rays are indiscriminately destructive, so that if enough 

 is allowed to circulate in the bodv to destrov cancer 

 cells, the normal cells of the body will also be 

 destroyed. It must be allowed, however, that the 

 observations upon which this postulate are founded are 

 by no means conclusive, and though there is no doubt 

 that the alpha and soft beta rays destroy normal cells 

 far more readilv than is the case with the gamma 

 rays, it may still be true that they too possess some 

 degree of selective action, it the dosage be regulated 

 with sufficient accuracy. 



This branch of therapeutics is still in its infancy, 

 and it would be a mistake either to raise delusive 

 hopes because some cancerous growths have been 

 made to disappear under its use or to declare it use- 

 less because disappointments are common. One 

 NO. 2103, VOL. 82] 



disease, rodent ulcer, is cured by the use of radium in 

 the great majority of cases, only a few rodent ulcers 

 proving refractory to its use. There are, however, 

 other methods of curing rodent ulcer. The further 

 development of this branch of medical science will be 

 watched with great interest. 



.4 SIMPLE METHOD OF ELECTROPLATING. 



AT a meeting of the Royal Society of .\rts on 

 February 2, a paper by Mr. A. Rosenberg was 

 read upon an improved method of electroplating. Mr. 

 Rosenberg dispenses altogether with the plating bath 

 and all external sources of electricity. The plating 

 is carried out simply by rubbing on a powder moistened 

 with water. The process is really a refinement of 

 the old contact method. It will be remembered that 

 in this process a piece of metal which it is desired to 

 plate upon is immersed in an electrolyte, for example, 

 one containing a silver solution. In contact with this 

 metal a more electropositive one is placed, also dipping 

 into the electrolyte. This metal, usually zinc, passes 

 into solution, and an electric current thereby is 

 generated. The silver is then plated-out upon the 

 less electro-positive metal. 



.Mr. Rosenberg employs his electro-positive metal in 

 the form of a fine powder, and generally uses 

 magnesium. This is mixed with a metallic salt or 

 with the powdered metal it is desired to plate-out, and 

 ammonium sulphate or other ammonium salt. In 

 order to plate a piece of metal the powder is moistened 

 with water and rubbed over its surface by means of a 

 piece of rag or a brush. By this means adherent and 

 bright deposits are obtained in about one minute, the 

 thickness of the deposit depending upon the time em- 

 ploved and the quantity of powder used. 



The magnesium, being strongly electro-positive, 

 reacts with the moist electrolyte, and goes into solution, 

 causing the metal to be plated-out upon the metallic 

 surface which is being rubbed. In other words, each 

 particle of the powdered magnesium may be said to 

 function as a minute anode. One of the difficulties in 

 electroplating is to plate a substance upon itself. It 

 is easv enough when plating has once commenced, 

 say on a spoon, to give it almost any thickness of 

 deposit ; but if the spoon is once withdrawn from the 

 bath and used, it cannot be plated further without 

 first stripping off the old deposit. Mr. Rosenberg 

 claims that with his process this difficulty does not 

 occur. 



.Another great difficulty in electroplating is the 

 cleansing of the article to be plated ; the least trace 

 of grease, even that produced by handling, for ex- 

 ample, will prevent an even and adherent deposit. 

 Consequently, articles have, as a rule, to be chemically 

 and mechanically cleaned before being put into the 

 plating bath. \Vith the powder, " Galvanit," of Mr. 

 Rosenberg this is not necessary, because the act of 

 rubbing the powder carries out its own cleansing. 



The author's object has been to produce a house- 

 hold method of plating. Thus, when the tinning of 

 •saucepans is worn out, the householder has only to 

 polish the inside with the moist "tin Galvanit" to re- 

 tin the saucepan. Spoons from which the silver- 

 plating is partly worn can be re-plated. The "nickel 

 Galvanit " can be used for bicycles and so on. Mr. 

 Rosenberg demonstrated the process before the meet- 

 ing by plating an iron tube with cadmium, a copper 

 tube with nickel, a penny with silver, and a brass tube 

 with tin. 



" Galvanit " can also be used for nickel-facing 

 electrotypes. The process is certainly ingenious, and 

 will no doubt be found useful for small work, but it 



