208 REPORTS ON THE STATE OF SCIENCE.—1913. 
cannot be ignored, and it is likely that some of the anomalous results of 
fatigue tests may be due to it. It is remarkable that Stanton’s repeated 
shock tests (No. 83) should give results at least as consistent as those of 
tests in which the stresses are not (or are intended not to be) impulsive. 
59 Reynolds, O., 1902 On a Throw Testing Machine for Reversals of Stress. 
and ‘Phil. Trans.,’ A, 199, 1902. ‘Sci. Abs.,’ 1903, 
Smith, J. H. No. 1302. 
Two of the chief conclusions have been contradicted by subsequent 
work. These are :— 
That under a given range of stress the number of reversals before rupture 
diminishes as the frequency of reversals increases. That ‘hard’ steels 
will not sustain more reversals with the same range of stress than mild steels 
when the frequency is high. 
Some vibration of machine or specimen is supposed to be responsible 
for the above results. See remarks by Messrs. Stanton and Pannell, No. 84, 
pages 10 and 11. 
60 Ritchie, J. B. 1910— Dissipation of Energy in Torsionally Oscillating Wires ; 
ll Effects Produced by Change of Temperature. ‘ Proc. 
Roy. Soc. Hd.,’ 31, 1910-11. ‘Sci. Abs.,’ 1911, 
No. 1310. 
61 Do. 1910— Apparatus for Inducing Fatigue by Repeated Exten- 
Il sional and Rotational Strains. ‘Proc. Roy. Soc. 
Edinburgh,’ 31, 1910-11. ‘Sci. Abs.,’ 1911, No. 1311. 
For Nos. 60 and 61, see Report, Appendix I. 
62 Rogers, F. 1905 Heat Treatment and Fatigue of Steel. ‘Journ. Iron 
and Steel Instit.’? 1905. ‘Sci. Abs.,’ 1905, No. 1805. 
Tests on rotating cantilever (Wohler pattern) machine, 400 r.p.m. Three 
grades of steel tested. 
See Report, note on ‘ Heat Treatment.’ 
63 Rogers, F. 1906 Microscopic Effects produced by the Action of Stresses 
on Metals. ‘Soc. d’Encouragement Rev. de Metal- 
lurgie Mém.,’ 3, Oct. 1, 1906. 
Further details, with micrographs of the work of No. 62. Suggested 
reasons why slip lines in iron and steel should be ‘ broken.’ 
See Report, Note on Heat Treatment. 
63a Rogers, F. 1913 So-called Crystallisation through Fatigue. Read before 
Iron and Steel Institute, September 1913. 
64 Roos, J. O. 1912 On Endurance Tests of Machine Steel. Intern. Assoc. 
Testing Materials. Paper V. 24, 1912. 
65 Do. 1912 Some Static and Dynamic Endurance Tests. Intern. 
Assoc. Testing Materials. Paper V. 2B, 1912. 
Two series of tests made on same material :— 
(1) With rotating-bar machine of Wohler type. Speeds, 1,200 and 2,400 
r.p.m. 
PO) In a machine of author’s design. Blows were given by hammers 
striking a specimen alternately on either side. The maximum stresses 
were calculated from the height of fall of hammer, on the assumption that 
the whole energy of blow was taken up as elastic energy of the piece. 
Material, steels of 0-10, 0-40, 0-65 per cent. of carbon, on which tests were 
made after ‘annealing’ and also after oil-tempering. 
In (1) the endurance was rather higher with the higher speed. 
In (1) and (2) the oil-tempered specimens had much greater endurance. 
The ‘f, » curves’ for (1) and (2) corresponded very closely, confirming 
Stanton’s (No. 83) result, that So may be taken as a measure of the re- 
sistance to repeated shock, / being the ‘ real’ (natural) elastic limit. 
66 Rosenhain, W. 1911 Two Lectures on Steel. ‘Proc. Inst. Mech. Eng.,’ 
Pt. IL., pp. 280-83. 
Remarks on resistance of steel to alternating stress. 
