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SCIENCE. 



[N. S. Vol. V. No. 111. 



steel that those most in use are hardly as 

 satisfactory as could be desired. The stud- 

 ies of Phillips* conclusively show that when 

 using the evolution method the whole of 

 the sulphur content is not given off in such 

 a form as to be retained by the usual means 

 employed to catch the gas. It seems not 

 too much not to say that it is hazardous to 

 use the evolution method on pig or cast 

 iron, even when fusion of the residue is em- 

 ployed. 



The formation of unoxidizable gases con- 

 taining sulphur in the application of the 

 evolution method to steel has not, so far as 

 our knowledge goes, yet been demonstrated, 

 and accordingly the evolution method is 

 still used largely on steels. But on pig and 

 cast irons the oxidation method seems the 

 only one applicable, and some recent studies 

 of Blair, described in a paper at this 

 meeting, indicate that on certain pig irons 

 all the sulphur is not given even by this 

 method, unless the graphitic residue is 

 fused with sodium carbonate and niter. 

 Both methods are somewhat slow, and there 

 is need of further study. If some means 

 could be found by which barium sulphate 

 could be readily and accurately converted 

 into sulphide, so that a volumetric method 

 could be applied to this sulphide, it would 

 be a decided step forward. The necessity 

 in accurate work for purifying barium sul- 

 phate, as first obtained from almost any 

 solution, by fusion and reprecipitation, adds 

 quite considerably to the time required. 

 With steels and two sets of evolution ap- 

 paratus, using bromine for oxidation, two 

 determinations may be made in two hours. 

 With four sets of evolution apparatus one 

 operator can make twelve determinations in 

 a day. In these cases purification by fusion 

 is not attempted. By the oxidation method 

 on pig or cast iron two determinations re- 

 quire about five liours, while one operator, 



* Tlie Journal of the American Chemical Society, 17, 

 891. 



with a supply of borings ahead and suffi- 

 cient appliances, can get from ten to twelve 

 results in a day. With this output purifi- 

 cation by fusion is not attempted. If this 

 is done, the time for a pair of determina- 

 tions must be extended an hour and a half, 

 and the daily output would be cut down at 

 least a third. 



From what has preceded in this hasty 

 and necessarily imperfect survey of a por- 

 tion only of the analytical methods in use 

 in the iron and steel industry, it is clearly 

 evident that there still remains an enor- 

 mous amount of work to' be done in connec- 

 tion with methods. We have touched upon 

 only five of the fifteen or twenty constit- 

 uents occurring in and affecting the quality 

 of iron and steel, and find the methods for 

 determining even these more or less imper- 

 fect and needing more work. What will 

 be our condition as chemists if, as seems 

 probable, nickel, chromium, aluminum, 

 tungsten, and the gases, oxygen, hydrogen 

 and nitrogen, either free or combined, with- 

 in the next few years, come into promi- 

 nence as constituents of iron and steel, and 

 are made elements in important commercial 

 contracts ? Still further thus far our meth- 

 ods are concerned almost entirely with the 

 total content of the various constituents 

 we are determining. We know very little 

 about the compounds of the various con- 

 stituents occurring in iron and steel, with 

 the metal or with each other. Is the 

 phosphorus present as phosphide or phos- 

 phate, or both ? How besides as sulphide 

 does the sulphur occur? Do the various 

 carbides which are revealed by the micro- 

 scope, and whicli are believed to be so 

 closely dependent on the heat treatment 

 which steel receives, and which are so inti- 

 mately related to the value of the metal, 

 differ from each other in carbon content, or 

 only in crystalline form ? Who will be the 

 first to isolate any of these carbides ? Who 

 will first give us a practicable, accurate and 



