clxx Proceedings. 



coast of Jersey, in wbicb the structure showed a gradation from 

 the laminated lava-flow form to the spherular bodies of various 

 sizes which occur in this rock. Crystals of olivine, quartz, 

 felspar, &c., were also referred to, and their characteristic forma 

 and structure shown by the optical lantern. 



Seiitcmher 9th. — Four short papers were read at this meeting, 

 %iz. : — "On the occurrence of larvae of the Goat Moth, Cossus 

 luiniperda," by Mr. W. Murton Holmes ; " On the Sand-wasp, 

 Amwophila mbnlosa," by Mr. C. H. Goodman ; " On a double 

 nest of the Great Tit built in my garden at Addiscombe," by me ; 

 nnd " On the use of the Storm Petrel as candles in the Shetland 

 Islands," also by me. These papers will appear in e.vtemo 

 (Trans., Arts. 95, 96, 97, and 98). 



October lith. — " On a new Sense," by Mr. Augustus Wheeler, 

 being the history and growth of spectrum analysis, with some of 

 its applications to the arts and sciences, illustrated by means of 

 the optical lantern. After a reference to the nature of light, the 

 lecturer proceeded to trace the history and growth of the science 

 of Spectroscopy from the great discovery of Newton of the com- 

 posite character of light to its refinements at the present day. 

 Having described the construction of several of the various forms 

 of spectroscope now in iise, and touched upon some of their appli- 

 cations in the arts, he concluded by devoting some time to the 

 consideration of the very important aid this branch of science 

 has rendered to Astronomy, giving the greater prominence to 

 the measures of motion in the line of sight, in both the solar and 

 stellar economies, which this method has rendered possible, 

 laying special emphasis on the recent discoveries of invisible 

 companions of variable and double stars which were not hitherto 

 suspected of being binaries, but which have been proved to be so 

 by their motions as revealed by the spectroscope. The lecture 

 was illustrated with a large number of lantern slides, several of 

 which were actual photographs of spectra, and of the heavenly 

 bodies themselves. 



November 2nd. — "On the Polarization of Light, illustrated 

 with numerous brilliant slides by means of the Optical Lantern," 

 by Mr. J. J. Briginshaw. This very interesting paper, after 

 dealing with the principles of polarization and the invention of 

 the apparatus as adjusted to the microscope, proceeded to show, 

 by means of numerous slides of great beauty, how certain colours 

 and changes of colour were capable of being produced ; and also 

 how the power of exhibiting colours could be utilised for the de- 

 tection of minute mineral crystals in thin sections of rock ; as 

 well as for showing the structure of metallic and other crystalli- 

 sations when formed by themselves. The lecturer showed a 

 pretty experiment in the displacement of the atoms in glass, and 

 consequent polarization caused by pressure, thus illustrating the 



