April 1, 1904.] 



SCIENCE. 



531 



decades, its advance has been at the rate 

 of about 200 feet annually. The flood 

 plain deposits of the upper Po are cross 

 bedded and very irregular; the beds are 

 chiefly cobbles, coarse gravel and pebbles; 

 occasionally wedges of sand are thrust in, 

 the latter of limited extent. The beds show 

 great variations in size of materials ; there 

 are sudden changes from eoai'se to fine 

 gravel, and vice versa. The beds are not 

 continuous over wide areas ; generally there 

 is a change in composition and texture 

 every few rods. Occasionally there are' 

 local deposits of silt and clay, stratified as 

 a rule, which cover a few acres. One of 

 these deposits in the environs of Turin 

 covers forty acres. On the lower Po the 

 flood plain deposits are much finer in tex- 

 ture and show more regular arrangement 

 than those quoted above. Much of the 

 material is silty clay and fine sand. Lam- 

 inated structure is common, the thin lam- 

 ina extending for several hundred feet, but 

 invariably replaced sooner or later by sedi- 

 ments of different texture or composition. 

 When long sections are exposed so that 

 they can be seen ensemble, it is noticeable 

 that the beds undulate. Strictly speaking, 

 there is no liorizontality of beds, but rather 

 a slow rise and fall. Long, flat augen of 

 sand are the apparent cause of this ar- 

 rangement. These flat lenses occur fre- 

 quently, the finer sediments wrap them 

 about, and the bedding of the latter is made 

 to show corresponding undulations. The 

 degree of Tindulation is determined by the 

 thickness and length of the sand lenses. 



Naniucltet Shore Lines, II.: F. P. Gul- 

 liver. (Illustrated with lantern views.) 

 During the past year the writer has con- 

 tinued his studies of the recent changes in 

 the shore lines of the island of Nantucket, 

 and the results of such study are given in 

 this paper. Details of changes are pre- 

 sented in the following areas : Great Point, 



Coskata, Haulover Break, Surfside, Mad- 

 daket. Smith Point, Brant Point, Nan- 

 tucket Harbor and Coatue. Original plane 

 table surveys are given of Miacomet fore- 

 land, at Surfside, where sand has been 

 built out some 1,500 feet in the last forty 

 years in one of the most exposed portions 

 of the island, while extensive cutting back 

 has taken place both east and west of this 

 foreland; and also of Smith Pond, where 

 the shore line is rapidly moving to the 

 north. Since the break was made in the 

 tombolo at the head of the harbor connect- 

 ing Coskata Island with the eastern end of 

 Nantucket, in the winter of 1896-7, at the 

 point where the fishermen formerly hauled 

 their boats over the sand, there have been 

 many changes in the shore lines. The facts 

 in regard to these changes have been col- 

 lected from government surveys and many 

 private sources, and a series of outline 

 maps prepared. 



The New Geology under the New Hypoth- 

 esis of Earth Origin: Herman L. Fair- 

 child. 



A theoretical discussion of the geologic 

 bearings of the planetessimal hypothesis. 

 A brief comparison is made between the 

 two conceptions of earth genesis, and it is 

 shown how the nebular hypothesis has 

 failed to explain phenomena and has been 

 a hindrance to the progress of geologic 

 science. Some of the topics discussed are, 

 origin of the atmosphere, origin of the 

 ocean, volcanic phenomena, source of hy- 

 drocarbons, geologic climates, diastrophic 

 movements, life on the earth. 



The Hnniboldt Region; a Study in Basin 



Range Structure: G. D. Louderback. 

 Glacial Erosion in the Finger Lake Region, 



Neiv York: M. R. Campbell. (Eead by 



title.) 



The Finger Lake region of New York is 

 an ideal field for the study of the effect of 

 glacial erosion, presenting as it does simple 



