Proceedings of Learned Societies. 457 



admirable both, in design and execution. The earnest boy tracing 

 bis mathematical diagrams on the stone hearth, unconscious that 

 his father and two visitors are watching him; the calm, thoughtful 

 satisfaction of the parent, who is hopefully speculating on his child's 

 future career, and the varied expression of the two ladies, are pre- 

 sented to us by the artist with a force and fidelity seldom seen in 

 more pretentious works. 



The Abbeville Jaw : An Episode in a Great Controversy. By 

 J. L. Rowe, F.G.S. (Longmans.) — This is a paper read before the 

 Hull Literary and Philosophical Society. The author is a bit of a 

 humourist, and his chief object seems to be to promote a sort of 

 compromise between those who assign a brief date to man's 

 existence, and those who claim for him a long antiquity. 



Rambles in Search of Flowerless Plants. By Margaret 

 Plues. (Cottage Gardener Office, Houlston and "Wright.) — This 

 handsome and elegantly illustrated volume is a good specimen of 

 a class of works to which the popularization of science is mainly 

 due. It affords just the sort of help that beginners want, and will 

 be very useful in country trips. The subjects range from ferns to 

 mosses, algae, lichens, and fungi. Miss Plues writes in an interest- 

 ing, agreeable style ; and her directions for the finding of objects 

 and the identification of species are judiciously conveyed. Those 

 who want instructions for collecting a class of objects of great micro- 

 scopic interest, will find an additional reason for thanking an 

 accomplished lady for her instructive work. 



PROCEEDINGS OF LEARNED SOCIETIES. 



BY W. B. TEGETMEIER. 



ROYAL INSTITUTION.— May 13. 



On the Mechanical Effects of Gun Cotton. — In the May 

 number of the Intellectual Observer, page 302, will be found an 

 account of Professor Abel's lecture at the Royal Institution, " On 

 the Chemical Properties and Preparation of Gun Cotton." Mr. 

 Scott Russell has supplemented this lecture by a second*" On its 

 Mechanical Action and General Practical Utility." Gun cotton, as 

 prepared by the Austrian process, is uniform in quality and perma- 

 nent in action ; it possesses the greatest cleanliness in use, not foul- 

 ing the gun as gunpowder does, and hence possesses great advan- 

 tages for use with breech-loading arms. 



Exploded in the open air it acts differently from gunpowder ; if 

 the latter is. exploded in one pan of a pair of scales, the arm of 

 the balance is violently depressed. An equal weight of gun cotton, 



