284 Proceedings of Learned Societies. 



cliff, and, from the formation of the latter being alternating beds of 

 clay and limestone, they are rapidly falling in and wasting away; 

 indeed, so much so, that in all probability scarce a vestige of the 

 remains will appear after the usual high tides of the spring." 



PROCEEDINGS OF LEARNED SOCIETIES. 



BY W. B. ■ TEGETMEIER. 



CHEMICAL SOCIETY— March 2. 



Action of Silicate of Soda on Cotton. — The injnrions action 

 of the soluble glass or mineral sizing used in cotton printing is well 

 known, the strength and durability of the fabric being materially 

 injured by its employment. Dr. Crace Calvert considered that the 

 injury depends on the deposit of liberated silica in. the cotton cells, 

 and that the fibre is then weakened by the caustic action of the free 

 alkali. Drs. Erankland and Abel, on the other hand, differed from 

 Dr. Calvert, regarding the intpiiry as being of a mechanical rather 

 than a chemical character, and as being due to the expansive force 

 exerted by the carbonate of soda as it crystallizes, after being set free 

 from the silica. The consideration of this subject is an important 

 one, in a domestic as well as a manufacturing point of view, as the 

 employment of the crystallized carbonate of soda used in washing is 

 known to have a very injurious effect on the strength of cotton 

 fabrics washed by its aid, unless it is completely removed by pure 

 water before the process of drying. 



GEOLOGICAL SOCIETY.— March 8. 



The Eossils of Windmill Hill, Gibraltar. — A very interesting 

 communication was received from Mr. Busk and the late Dr. Fal- 

 coner on the fossils of the Genista Cave of the Rock of Gibraltar. 

 The authors stated that the rock abounds in both seaboard and inland 

 caverns, the Genista Cave being one of the latter class. It has been 

 traced downwards to a depth of 200 feet, but the external aperture 

 has not yet been discovered. It was stated to be full of the remains of 

 quadrupeds and birds, some of the former being now wholly extinct ; 

 others, as the Hycena hrunea, are now extinct in Europe, and repelled 

 to distant regions of the African continent; while others again 

 live now either on the rock or in the adjoining Spanish peninsula. 

 It was inferred that there had been a connection by land, either cir- 

 cuitous or direct, between Europe and Africa at no very remote 

 geological period. The authors observed that the wild animals 

 whose remains were discovered evidently lived and died upon the 

 rock during a long series of ages. 



