SCIENCE-GOSSIP. 



261 



terrible disturbances, such as that of the Lisbon 

 earthquake, which affected a region as large as 

 Europe, must be regarded as due to a more 

 powerful and far-reaching agency. Volcanoes and 

 earthquakes seem, certainly, to be related to each 

 other, though volcanoes do not cause earthquakes, 

 yet the forces which produce one manifestation 

 may, when acting under different conditions, give 

 rise to the other. Local earthquakes are frequently 

 observed to precede volcanic eruptions. 



While the exact cause of earthquakes must be 

 considered a matter for future research and investi- 

 gation, there seems to be little doubt that their 

 origin is connected with the causes which give rise 

 to earth foldings and the production of mountain 



chains. Long continued pressure, due to enormous 

 masses of superincumbent rock, produces, at last, 

 rupture at the point or area of least resistance. 

 Thus a sudden jar is produced, probably with rents 

 and fissures, and this squeeze, suddenly relieved, 

 causes a sharp compression, followed by a relaxation, 

 and this being transmitted successively to neighour- 

 ing portions of rock causes a wave movement of 

 earth compression to travel along the upper portion 

 of the earth's crust. The gradual cooling of the 

 earth and the consequent contraction of its 

 material, has been brought forward as an explana- 

 tion of the stresses in the crust, which may lead to 

 rupture followed by earthquake shocks. 

 7, Mountvitw Road, Crouch Hill, London, N. 



A NEOLITH'S HAUNT. 

 By Alexander J. Hogg. 



T N Dr. Darwin's treatise on earthworms, the 

 author draws attention to the fact that in 

 meadows and unfilled places, where earthworms 

 abound, the surface of the soil is being continually 

 raised by their ex- 

 cretions ; so that in 

 the course of a few 

 years, any object left 

 upon the surface be- 

 comes enveloped by 

 the ever - growing 

 humus, and finally 

 disappears from view 

 as though swallowed 

 up by the earth. 

 Darwin also men- 

 tions that in woods 

 the worms are not 

 plentiful, as there, 

 the products of the 

 decaying leaves are 

 injurious or unpalat- 

 able to them ; and 

 the soil therefore, in 

 such situations, in- 

 creases at a much 

 slower rate than on 

 grass-land. 



Of the many con- 

 firmations of these 

 facts which are ob- 

 servable in our walks, I know of none more 

 striking than to meet, in some wind-swept spot 

 amid the trees, with the flint weapons or tools of 

 the neolithic hunter, lost or cast away in passing 

 along the track through the woodland haunt, 

 perhaps thousands of years ago, and lying 



L 



Neolithic Remains from Surrey. 



unregarded for untold generations. Such objects 

 are frequently found in the remnants of the 

 great pre-historic forests that once surrounded 

 Croydon, now represented by small patches of 



woodland covering 

 the tops, or extend- 

 ing along the flanks 

 of the hills ; and 

 preserving, unvexed 

 by the plough, the 

 surface on which 

 our far-away an- 

 cestors dwelt. 



It was in the spring 

 of 1894, when the 

 primroses were al- 

 most fully - blown , 

 and the young spikes 

 of the wild hya- 

 cinths began to 

 stand up among 

 their glossy leaves, 

 that, on the out- 

 skirts of one of these 

 woods, I came, un- 

 awares, upon the spot 

 where a neolithic 

 worker had been 

 engaged in making 

 his implements. My 

 attention was at- 

 tracted by the number of flint chips lying 

 scattered over the ground within a very limited 

 radius. Under and around a small oak stub lay 

 hundreds of chips and flakes, with a few perfect 

 implements, and many irregularly-shaped frag- 

 ments of the crust, or outside coating of chalk- 



