288 Proceedings of Royal Society of Edinburgh. [sess. 
point slowly shifts towards the concentration origin with rise of 
temperature. 
Barium Hydroxide. 
Grams of 
substance in 
100 grams 
Solution. 
Temp. 
t° C. 
Density 
grams per c.c. 
Volume of 
1 gram of 
Solution at 
t° C. (V c.c.). 
Volume at t° 
0. of water in 
1 gram Solu- 
tion (V' c.c.). 
Expansion 
V-V' c.c. 
•89387 
15 
1*01079 
•98933 
•99192 
- -00259 
20 
1-00998 
•99010 
•99281 
- -00271 
5 } 
26 
1-00847 
•99160 
•99423 
- -00263 
5 J 
30 
1-00721 
‘99285 
•99537 
- -00252 
•08212 
15 
1-00000 
1*00000 
1-00005 
- -00005 
20 
•99913 
1-00087 
1-00095 
- -00008 
26 
•99766 
1-00234 
1-00238 
j - -00004 
•04303 
30 
•99656 
1-00345 
1 00352 
- -00007 
15 
•99957 
1-00043 
1-00044 
j - -ooooi 
J ? 
20 
•99870 
1-00130 
1-00134 
- -00004 
26 
•99728 
1-00273 
1-00276 
- -00003 
5 > 
30 
•99611 
1 *00390 
1-00392 
- -00002 
It thus appears that all the solutions of barium hydrate examined 
have a negative expansion. This hydrate is thus so far analogous 
to sodium hydrate. The effect of temperature on the expansion is 
not very marked, and for the last two concentrations the numerical 
values of the expansions are subject to considerable variations in 
the fifth decimal place, although they all agree in giving negative 
expansion (see fig. 2). 
Strontium Hydroxide. 
Grams of 
substance in 
100 grams 
Solution. 
Temp. 
t°C. 
Density 
grams per c.c. 
Volume of 
1 gram of 
Solution at 
t° C. (V c.c. ). 
Volume at t° 
C. of water in 
1 gram. Solu - 
tion (V' c.c.). 
Expansion 
V-V' c.c. 
•32744 
15 
1-00363 
•99639 
•99759 
- -00120 
? , 
20 
1 -00263 
•99738 
•99848 
- -ooiio 
26 
1-00114 
•99886 
■99992 
- -00106 
30 
•99996 
1-00004 
1-00105 
- 00101 
12162 
15 
1-00072 
•99923 
•99965 
- *00042 
20 
■99971 
1-00029 
1-00055 
- -00026 
26 
•99831 
1-00169 
1-00197 
- -00028 
30 
•99708 
1-00293 
1-00313 
- -00020 
•02354 
15 
•99946 
1-00054 
1-00063 
- -00009 
20 
•99849 
1-00151 
1-00153 
- *00002 
26 
•99700 
1-00306 
1-00296 
+ -oooio 
? J 
30 
•99600 
1-00432 
1-00411 
+ -00021 
