47 
of Edinburgh, Session 1872-73. 
With one exception these results indicate a logarithmic relation 
between the stiffness (S) and the tension (T) of the form 
S 0 - S oc a~ T . 
Here S 0 is the stiffness when the tension is very great. 
Thus, taking the numbers in experiments (b) and (Z) above, we 
obtain the following comparison with experiment of the formula — 
68 - S = 6P5 x (§) 100 ° . 
T 
1950-8 = 1987 x (1-08) ,0 '““ 
Experiment. 
Formula. 
Experiment. 
Formula. 
41 
41 
182 
184 
28 
27*3 
171 
170 
18 
18*2- 
155 
158 
12 
12-1 
142 
146 
8 
8 
132 
135 
4 
2-4 
125 
125 
Considering the excessively uncertain nature of such experi- 
ments, these results may be looked upon as agreeing well with the 
law suggested. 
2. Preliminary Sketch of the Thermo-electric Diagram for 
Iron, Gold, and Palladium. 
3. On the Muscles which open and close the Mouth, with 
some Observations on the Active and Passive Condition 
of Muscles generally. By Dr Gamgee. 
4. Observations and Experiments on the Cerebral Hemi- 
spheres and Corpora Striata of Birds. By Dr M‘Kend- 
rick. Communicated by Professor Turner. 
Surgeon-Major Black exhibited twenty-five large photo- 
graphic views of the late eruption of Mount Vesuvius, which 
had been executed by his brother, John Melton Black, Esq. 
VOL. VIII. 
