Dr. A. M. Mayer on the Experimental Determination 



Carbo 



■{ 





Pig iron. 



Spiegeleisen 



Graphite . 



3-01 



025 



Combined . 



. 033 



401 



Silicon . 



3-01 



0-49 



Sulphur 



. 0-06 



0-04 



Phosphorus 



0-0.2 



0-25 



Manganese 



0-42 



10-15 



Copper 





trace 



Iron . . 



93-15 



84-81 



100-00 



100-00 



It is very difficult to understand why these lines, which are 

 not those of carbon, should disappear at the exact point at which 

 the blast ought to be stopped, and that they should be due to a 

 substance of which so little can be present. The following ana- 

 lyses of the metal at different stages in the process, quoted from 

 Mr. Snelus's paper read at the Meeting of the Iron and Steel 

 Institute in December 1870, show that in some cases the quan- 

 tity of manganese present is inappreciable : — 











Before adding 





Pig 



6 minutes 



9 minutes 



Spiegel, 13 mi- 





used, after starting. 



after starting. 



nutes after 











starting. 



Car- J Graphite 

 bon. ^Combined 



207 









1-20 



2-17 



1-55 



0-097 



Silicon . 



1-952 



0-795 



0-635 



0-020 



Sulphur 



0-014 



trace 



trace 



trace 



Phosphorus 



0-048 



0-051 



0-064 



0-067 



Manganese 



0-086 



trace 



trace 



trace 



XI. On the Experimental Determination of the Relative Inten- 

 sities of Sounds; and on the Measurement of the Powers of 

 various substances to Reflect and to Transmit Sonorous Vibra- 

 tions. By Alfred M. Mayer, Ph.D., Professor of Physics 

 in the Stevens Institute of Technology, Hoboken, New Jersey, 

 U. S. A* 



TX7HILE the problems of the determination of the pitch of 

 VV sound and the explanation of timbre have received their 

 complete elucidation at the hands of Messenne, Young, De la 

 Tour, Konig, and Helmholtz, the problem of the accurate expe- 

 rimental determination of the relative intensities of given sono- 

 rous vibrations has never been solved. 



* Communicated by the Author, having been read before the National 

 Academy of Sciences at Cambridge, Massachusetts, November 21, 1872. 



