58 JOURNAL or THE PLYMOUTH INSTITUTION. 



General notion of the construction of the spectroscope, and the 

 mode of using it. Application to various purposes, as the Bessemer 

 process of manufacturing steel, and its use in combination with 

 the microscope in detecting the presence of exceedingly minute 

 quantities of many bodies. 



Kirchoff's researches into the nature of the dark lines of the 

 solar spectrum were explained, and the application of the spectro- 

 scope to various interesting and important astronomical subjects 

 was considered. 



The lecturer noticed the independent discovery by Lockyer and 

 Janssen, of the possibility of determining, by the aid of the spec- 

 troscope, the presence of those remarkable red prominences in the 

 sun, which had till recently been visible only during total eclipses, 

 and concluded with a reference to the observations made on the 

 fixed stars, nebulae, and comets. 



OUK BEAINS. 



ABSTRACT OF MR. W. SQUARE'S PAPER. 



This paper may be considered as naturally divided into two parts 

 — abstract and physical, immaterial and material ; the first is con- 

 veyed in the phrase, ''So-and-so has brains;" the second in the 

 sense of brain - matter, the actual contents of the skull. In order 

 to come to any understanding at all of the abstract, the material 

 must first be explained, and afterwards, as far as possible, its con- 

 nection with the abstract. 



In the term " brains " we must not merely include the contents 

 of the cranium, but all the nervous system. Roughly speaking, 

 we may divide the whole into two parts — white and grey matter; 

 the white for conduction, the grey for reception and perception of 

 impressions, and for origination of ideas and nervous force. 



The lecturer described the nervous system as analogous to the 

 electric telegraph — the nerves being the wires, the centres the 

 battery. The centres described were the spinal cord, the medulla, 

 and pons varolii ; the special centres, the cerebellum ; and lastly 

 the cerebrum. Their anatomy in the human subject, and after- 

 wards their comparative anatomy, and the way in which, by the 

 development and addition of the various organs, the attributes of 

 the individual whole are increased, culminating in man, were then 



