Brown—The Densities and Specific Heats of some Alloys of Iron. 71 
TABLE X. 
NickEL-MANGANESE STEELS. 
Percentage Composition | Specific Volume 
Mark C Mn Ni | Density Observed Calculated Difference 
1109 D 0:8 5°04 14°55 7:8272 0:12776 0:12768 0:00008 
1414 A 0:6 5°04 19°00 778542 0:127382 0°12641 0:00091 
1414 B | 0°6 5:04 | 25:00 7°9101 | 0°12642 0°12554 0:00088 
In Table X. are given the results for three nickel steels which have each the 
same amount of manganese present, and nearly the same percentage of carbon. 
If the observed specific volumes be corrected for the presence of carbon and 
manganese, it will be found that these corrected points lie practically on the nickel 
curve in fig. 1, as might be expected from the results of the other high nickel 
steels given in Table IIL. 
CoNCLUSIONS. 
The following are the conclusions that may be drawn from these experi- 
ments :— 
1. Carbon when added to iron (up to about 0°2 per cent. of carbon) encreases the 
specific volume of the material at the rate of 0:0018 ¢.c. for every one per cent. of 
carbon added, and for higher percentages of carbon—up to about 1-25 per cent. 
—the inerease in specific volume is at the rate of 0°0015 c.c. per 1 per cent. of 
carbon present. 
2. Manganese when added to iron (up to about 2 per cent. of manganese) 
imereases the specific volume of the material by about 0:00026 c.c. per one per cent. 
of added manganese, and for higher percentages of manganese—up to about 
18°5 per cent.—the specific volume is decreased about 0:00015 c.c. per one per cent. 
of added manganese. 
3. Mickel when added to iron (up to 20 per cent. of nickel) has no effect on the 
specific volume of the material; but when between 20 and 31-4 per cent. of 
nickel is present, the specific volume of the material is decreased at the rate 
of about 0°00028 ¢.c. for every one per cent. of added nickel. 
4. Tungsten when added to iron (up to about 15 per cent. of tungsten) 
decreases the specific volume of the material by 0:0009 c¢.c. per one per cent. of 
added tungsten. 
