CONTENTS. 



NOTICES AND ABSTRACTS 



OF 



MISCELLANEOUS COMMUNICATIONS TO THE SECTIONS. 



MATHEMATICS and PHYSICS. 



Mathematics. 



Page 

 Professor Cayley on a Formula of M. Chaslea relating to the Contact of 

 Conies 1 



on the Problem of the In-and-circumscribed Triangle .... 1 



Mr. AxEXANDER J. Ellis on Stigmatics 2 



Professor Cremona on the Geometrical Transformation of Plane Curves. 

 (Communicated by Mr. T. A. Hirst.) 3 



Mr. T. A. Hirst on a Generalization of the Method of Geometrical Inversion 3 



Mr. M. MoGGRiDGE on an easy Mode of Measuring Heights 4 



Mr. W. H. L. Russell on Symbolical Expansions 4 



ASTEONOMT. 



Mr. W. R. BiBT on Methods of Detecting Changes on the Moon's Surface . . 4 



Rev. W. R. Dawes on the present Aspect of the Discussion respecting the 

 Telescopic Appearance of the Solar Photosphere 4 



Rev. Thomas Furlong on the Possibility of constructing Ellipsoidal Lenses 5 



Professor Hennessy on the possible Connexion between the EUipticity of 

 Mars and the general Appearance of its Surface 5 



Mr. R. W. Hardy's Speculations on Physical Astronomy 6 



Dr. Lee on an extensive Lunar Plain near the Montes Hercynii, which it is 

 proposed to name Otto Struve 6 



Professor Phillips, Notice of the Physical Aspect of the Sun 7 



Rev. T. W. Webb on a suspected Change of Brightness in the Lunar Spot, 



Werner 8 



■ on the Invisible Part of the Moon's Surface 9 



Light. 



Mr. J. Browning on a New Form of Spectroscope, in which Direct Vision is 

 obtained with a Single Prism 9 



