CONTENTS — (continued) . 



January 19, 1871. 



PAGE 



I. On the Structure and Development of the Skull of the Common Frog 



(Sana temporaria). By W. Kitchen Parker, F.R.S. 246 



II. Method of measuring the Eesistance of a Conductor or of a Battery, or of 

 a Telegraph-Line influenced by unknown Earth-currents, from a single 

 Deflection of a Galvanometer of unknown Resistance. By Henry 

 Mance, Superintendent Mekran Coast and Persian Gulf Telegraph De- 

 partment, Kurrachee 248 



III. Measurement of the Internal Resistance of a Multiple Battery by adjusting 



the Gralvanometer to Zero. By Henry Mange ........ 252 



IV. Modification of Wheatstone's Bridge to find the Resistance of <a Galvano- 



meter-Coil from a single deflection of its own needle. By Prof. Sir Wil- 

 liam Thomson, F.R.S. 253 



V. On a Constant Form of Daniell's Battery. By Prof. Sir William Thom- 

 son, F.R.S 253 



VT. On the Determination of a Ship's Place from Observations of Altitude. By 



Prof. Sir William Thomson, F.R.S. ............ . 259 



January 26, 1871. 



I. On the Mineral Constituents of Meteorites. By Nevil Story Maske- 

 lyne, M.A., F.R.S., Professor of Mineralogy, Oxford, and Keeper of the 

 Mineral Department, British Museum 266 



II. On the Organization of the Calamites of the Coal-measures. By W. C. 

 Williamson, F.R.S., Professor of Natural History in Owens College, 

 Manchester 268 



III. On Approach caused by Vibration. A Letter from Prof. Sir W. Thomson, 



LL.D., F.R.S., &c. to Prof. Frederick Guthrie, B.A 271 



List of Presents 273 



TAYLOR AND FRANCIS, RED LION COURT, FLEET STREET. 



