December 5, 1884.] 



SCIENCE. 



521 



seismograph of relatively moderate cost. The third 

 class will include ordinary non-instrumental observa- 

 tions according to a system to be prepared by Pro- 

 fessor Eockwood. It is expected that a considerable 

 number of the first and second class instruments will 

 be maintained by co-operation of public institutions 

 and government bureaus, at observatories, physical 

 laboratories, army arsenals and signal-service sta- 

 tions, and navy-yards ; while the instructions for the 

 general observations will be sent to all the regular 

 and volunteer observers of the signal-service, the 

 members of the state weather services, and to all 

 others who desire to aid in the work. In order to 

 concentrate work on the most profitable districts, a 

 chart of recorded shocks will be prepared by Professor 

 Eockwood ; and the selection of stations will then be 

 discussed by Messrs. Eockwood, Abbe, and Davis. 

 Further studies will be undertaken on the matters 

 of bibliography, previous observations, and instru- 

 ments; the whole work being under the direction of 

 the geological survey. 



— >The recent works of tbe U.S. geological survey, 

 and especially the remarkable report of Capt. Dut- 

 ton, have given an opportunity to Professor Traut- 

 schold of Moscow to draw a parallel between the 

 geological structure of Colorado and that of European 

 Russia, which appears in the bulletin of the Moscow 

 society of naturalists. In Russia the Silurian, 

 Devonian, carboniferous limestone, and lower Per- 

 mian series are marine deposits, while tbe upper 

 Permian is of fresh-water or terrestrial origin. The 

 trias and lower Jurassic rocks are also continental 

 deposits, or seem to be so to a great extent, while 

 the upper Jurassic groups are again of marine origin, 

 as is also the chalk, which contains only islands with 

 land vegetation. Three parts of the tertiary series 

 consist of terrestrial and fresh-water deposits, marine 

 deposits appearing only in the south; and the qua- 

 ternary is also a continental formation. Such being, 

 according to Professor Trautschold, the structure of 

 Russia, he had already concluded that in the north- 

 ern hemisphere there was a general retreat of the 

 sea during paleozoic times, and a growth of conti- 

 nents, upon which the carboniferous and then the 

 Permian floras largely increased ; European Russia 

 being, during the triassic and the first half of Ihe 

 Jurassic periods, a continent with nearly the same 

 outlines as now. During the second half of the 

 Jurassic period, another subsidence of the continent, 

 and an advance by it into the northern hemisphere, 

 again took place; without reaching, however, the 

 same level that it had had during the paleozoic 

 period, the sea remaining shallow. A second retreat 

 of the water took place during the tertiary and 

 quaternary periods. Similar oscillations might well 

 explain, in Professor Trautschold' s opinion, the 

 structure of the Grand Canon district, where the 

 connection between the Jurassic and triassic is as 

 close as in Russia. 



— From recent experiments to determine the abso- 

 lute force of the flexor muscles of decapod crusta- 

 ceans, Professor Felix Plateau of Gand, Belgium, 

 concludes that the absolute or static force of the 



muscles of the claws of crabs is relatively weak, and 

 that while the adductor muscles of some lamelli- 

 branchs are comparable with those of mammals, and 

 others with the more powerful muscles of the frog, 

 the muscles of the claws of crustaceans can be com- 

 pared only with the weakest muscles of the frog. 

 The relation between 

 the absolute force of 

 the muscles of man 

 and the greatest pow- 

 er Plateau had ob- 

 served in the crusta- 

 ceans, convinced him 

 that the contractile 

 force of the muscular 

 fibre is not the same 

 in all animals. Ar- 

 thropods are inferior 

 in this respect to 

 mammals and to la- 

 mellibranchs. Crus- 

 taceans, like insects, 

 have in proportion to 

 their weight much 

 greater power than 

 the vertebrates. 

 When experimented 

 on, as in the figure 

 given, he found that 



common crabs could raise from one to two and a half 

 kilograms, representing a force which he thought 

 clearly explained the mishaps undergone by these 

 animals. 



— The women medical students of Paris have pre- 

 sented a petition to the authorities for permission to 

 walk the hospitals, and become house-surgeons there- 

 in. The petition is supported by a considerable num- 

 ber of physicians and surgeons. 



— The ship Occidental, at San Francisco, lNov. 14, 

 reports, "At six p.m., Nov. 4, a hundred and fifty 

 miles off Mendocino, Cal., had three shocks of earth- 

 quake, and a few hours later two more heavy ones." 



— Mr. E. Knipping, meteorologist of the Imperial 

 meteorological observatory at Tokio, describes in the 

 September number of the Mittheilungen der deutschen 

 gesellschaftfiir natur- und volkerkunde Ostasiens, the 

 rapid development of weather telegraphy in Japan. 

 There are now twenty-four stations in the empire 

 connected by telegraph; and on the basis of their 

 observations, supplemented by despatches from China, 

 three daily synoptical maps are published in Japanese 

 and English characters. Observations are taken at 

 six a.m., and two and nine p.m., ' Japan ' time, which 

 is about that of the Kioto meridian ; so that the even- 

 ing observation corresponds to eight o'clock ' China 

 coast' time, six o'clock 'Bengal' time, four o'clock 

 ' Persian ' time, one o'clock ' German ' time, and noon 

 in 'English ' (Greenwich) time. The director of the 

 service is Mr. I. Arai; and the observers, telegraphers, 

 draughtsmen, and printers are all Japanese. The 

 first weather-map was printed on March 1, 1883, and 

 the tri-daily issue began a month later. The chief 



