[ 59 | 
VI. 
THE DENSITIES AND SPECIFIC HEATS OF SOME ALLOYS OF IRON. 
By W. BROWN, B.Sc. 
[ Read, June 18, 1907. } 
INTRODUCTION. 
Tue electric and magnetic properties of an extensive series of steels or alloys of 
iron were investigated in the Physical Laboratory of the Royal College of Science, 
Dublin, from 1895 to 1903; and the results were published at intervals in the 
Scientific Transactions of the Royal Dublin Society.* The alloys were all made 
at the Hecla Steel Works, Sheffield, and their chemical composition was 
determined in the Chemical Laboratory attached to the Hecla Works. 
For some time past the present writer has been investigating the thermal 
capacity of these various alloys, and has measured the densities and specific 
heats of about forty different samples; and the work done forms the subject 
of this communication. ‘The specimens were all carefully prepared and cleaned 
for these experiments; and to make sure that they would all be in the same 
physical state, they were raised to a bright red heat in a furnace, and dropped 
into water at about 16°C., then finally cleaned up, and polished with fine 
emery. 
In the chemical composition given in the following tables, it is assumed that 
in all cases on makes up the total to 100. 
Parr I.—DeEnsiry. 
For the determination of the densities of the specimens, a small specific-gravity 
bottle was specially made for the purpose. It is about 3 em. long and 1 cm. in 
diameter, with perforated stopper, and has a flange on the bottom, so as to enable 
* Barrett, Brown, and Hadfield, Scient. Trans. Roy. Dublin Soc., 1900, 1902, 1904. 
TRANS, ROY, DUB. S0C., VOL. IX., PART VI, M 
