W. H. FURLONGE ON MONOCULAR VISION. 41 



eye is seen by the other apparently projected upon the drawing- 

 pajDer on which it is looking. In fact, the question appears to me to 

 belong more to psychology, or at all events to the most recondite 

 physiological considerations of reflex nervous impressions, than to 

 practical microscopy. It is very probable, however, that some of 

 our members, and notably our President, are capable of throwing 

 light upon the cause of this remarkable phenomenon, which it 

 would be very desirable to obtain. My present object is simply to 

 bring the fact itself before the Club, to point out its practical bear- 

 ing upon our every-day work, and to suggest to some of our in- 

 genious mechanical members, who may have the time to devote to 

 the investigation, that it may be very possible to improve the 

 brilliancy of the image projected on the paper, and consequently 

 to increase the facility in tracing it, by the substitution of a very 

 truly and highly-polished plane metallic speculum, for the opaque 

 glass reflector I have described. 



The late Mons. A. de Brebisson. 



One of the Foreign corresponding members of the Club, Mons. 

 Alphonse de Brebisson, of Falaise, Normandy, died on the 26th 

 April last, at the advanced age of 74 years. His large and 

 valuable collection of some thousands of slides of Diatomaceas is 

 to be disposed of by his son, M. Bene de Brebisson. 



