PROCEEDINGS 
OF THE 
ROYAL SOCIETY OF EDINBURGH. 
SESSION 1918-19 
Part II] VOL. XXXIX. [PP- U3-208 
CONTENTS. 
NO. 
IX. On Hamilton’s Principle and the Modified Function in 
Analytical Dynamics. By G. H. Livens, M.A. Com- 
municated by Professor E. T. Whittaker, F.R.S., . 
(. Issued separately July 3, 1919.) 
X. The Cooling of the Soil at Night, with Special Reference to 
late Spring Frosts. By Captain T. Bedford Franklin, B.A. 
(Cantab.). Communicated by The General Secretary, . 120 
(Issued separately August 5, 1919.) 
XI. On the Presence of Formic Acid in the Stinging Hairs of the 
Nettle. By Leonard Dobbin, Ph.D., 137 
(Issued separately August 5, 1919.) 
XII. On the Mode of Action of Metal Sols. By Professor C. R. 
Marshall, 143 
(Issued separately October 20, 1919.) 
XIII. Some Conditions influencing the Reaction Velocity of Sodium 
Nitrite on Blood. By Professor C. R. Marshall, . . 149 
(Issued separately October 20, 1919.) 
XIV. The Propagation of Earthquake Waves through the Earth, 
and connected Problems. By Professor C. G. Knott, 
D.Sc., LL.D., 157 
(Issued separately October 21, 1919.) 
PAGE 
113 
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