FRAGMENTS OF SCIENCE. 



281 



Progress of the World. Monthly, Vol. I, No. 1. 

 October, 1895. New York : Progress of the World 

 Company, 156 Fifth Avenue. Pp. 156. 10 cents ; 

 $1 a year. 



Richards, Frank. Compressed Air. New 

 York : John Wiley & Sons. London : Chapman 

 &Hall. Pp.203. 



Risteen, A. D. Molecules and the Molecular 

 Theory of Matter. Boston and London : Ginn & 

 Co. Pp. 223. $2. 



Romanes, George John. Darwin and after 

 Darwin. II. Post-Darwinian Questions ; Hered- 

 ity and Utility. Chicago: Open Court Publish- 

 ing Company. Pp. 344. $1.50. 



Salazar, A. E., and Newman, Q. Estudios 

 Ijieniquos del Aire (Hygienical Studies of the Air). 

 Santiago, Chile. Pp. 20, with Plates. 



Scott, E. G. Reconstruction during the Civil 

 War in the United States of America. Boston 

 and New York : Houghton, Mifflin & Co. Pp. 

 482. $2. 



Sizer, Nelson. How to Study Strangers, by 

 Temperament, Face, and Head. New York : 

 Fowler & Wells Company. Pp. 367. $1.50. 



Smithsonian Institution. An Account of its 

 Origin, History, Objects, and Achievements. Pp. 



about 20, with Plates. The Exhibit of the In- 

 stitution at thj Cotton States Exposition, Atlanta, 

 1895. Pp. about 80. 



Stevens, W. Le Conte. Recent Progress in 

 Optics. Salem, Mass. : The Salem Press. Pp. 22. 



Stoddard, Charles Augustus. Cruising among 

 the Caribbees. New York : Charles Scribner's 

 Sons. Pp.198. $1.50. 



Stuver, E. Asexualization for the Limitation 

 of Disease, and the Prevention and Punishment of 

 Crime. Rawlins, Wyoming. Pp. 16. 



United States Life-Saving Service, Annual 

 Report of Operations, 1894. Washington : Gov- 

 ernment Printing Office. Pp. 470. 



Whiteley, R. Lloyd. Organic Chemistry. The 

 Fatty Compounds. New York and London : 

 Longmans, Green & Co. Pp. 285. 



Winterburn, Florence Hull. Nursery Ethics. 

 New York : The Merriam Company. Pp. 241. 



Wright, Carroll D., United States Commis- 

 sioner of Labor, and Gould, E. R. L. The Hous- 

 ing of the Working People. (Eighth Special Re- 

 p rtof the Commissioner of Labor.) Washington : 

 Government Printing Office. Pp. 461. 



Constituents of Ocean Bottoms. In his 



summary of the results of the Challenger 

 Expedition, Dr. Murray classifies marine de- 

 posits as littoral, shallow water, and deep 

 sea. Such deposits are, in origin, either 

 land-derived or pelagic that is, of the 

 ocean. The land-derived deposits edge the 

 shores, for the finest river mud is rarely met 

 with as far as three hundred miles from the 

 coast, and particles so large as to be called 

 sand remain close to it. Regarded in this 

 light, the whole ocean beyond the three-hun- 

 dred-mile belt of " territorial waters " pos- 

 sesses a distinct individuality, invaded by no 

 material of land origin except the mud and 

 boulders carried by drifting ice, the dust 

 which settles out of the air, and scraps of 

 floating pumice from volcanic eruptions. In 

 a few patches less than seventeen hundred 

 fathoms deep, far from land, the remains of 

 relatively large and delicate shells which 

 lived on the surface abound at the bottom, 

 mixed with innumerable shells of dense, 

 nearly microscopic foraminifera and a little 

 clayey matter, the whole receiving the general 

 name of pteropod ooze, from the characteris- 

 tic shells of pteropods which occur hi it. In 

 deeper waters no pteropod or other delicate 

 shells are found, and the calcareous meal of 



foraminifera, closely resembling softened 

 chalk, is called globigerina ooze, from the 

 particular genus of surface-living organ- 

 ism which occurs in largest proportion. At 

 greater depths globigerina ooze is found in 

 which the microscopic shells appear much 

 corroded ; and finally, in the deeps or areas 

 more than three thousand fathoms below the 

 surface, the deposit is almost free from car- 

 bonate of lime, and forms a stiff red clay 

 composed of decomposed volcanic or atmos- 

 pheric dust and those constituents of shells 

 that are not readily dissolved by sea water. 

 The process of formation has been clearly 

 shown. Over the whole surface the same 

 shell-bearing creatures die in myriads ; their 

 bodies fall continuously as a gentle calcare- 

 ous snow shower through the water, which 

 slowly dissolves them. The large thin shells 

 vanish first, and only reach the bottom in 

 shallow water ; the dense spheres of the pin- 

 head and smaller foraminifera resist longest, 

 and only the insoluble residue reaches the 

 greatest depth. Thus the excess of carbon- 

 ate of lime dissolved in the deepest layers 

 of the ocean is readily explained. The red 

 clay forms so slowly that particles of metal- 

 lic dust from exploded meteorites, which are 

 covered up by the surface accumulations 



