238 



SCIENCE. 



[Vol. VII., No. 162 



of Japan, vol. viii. 1885, contains a long paper 

 by Professor Milne, in which he has collected a 

 detailed description of ten series of experiments 

 carried on at different times from 1881 to 1884, for 

 the purpose of investigating phenomena connected 

 with earth vibrations. The experiments were all 

 performed in or near the city of Tokio, and con- 

 sisted in originating artificial earth vibrations, 

 usually by dropping a heavy weight or by ex- 

 ploding dynamite, and then studying the circum- 

 stances of their propagation by means of the 

 various seismographs which have been devised 

 by himself or his co-workers in Japanese seis- 

 mometry. It appears that the first effect upon a 

 seismograph with a single index is an impulse in 

 a normal direction ; and, similarly, a bracket seis- 

 mograph arranged to indicate normal motion be- 

 gins its indications before a similar seismograph 

 indicating transverse motion, implying that the 

 normal wave travels more rapidly than the trans- 

 verse. Near to an origin, the normal motion is first 

 outwards, then inwards, and the motion inwards 

 is greater and more rapid than the motion out- 

 wards ; while, at a distance from an origin, the 

 first motion may be inwards, and the two phases 

 are practically of equal amplitude. Roughly speak- 

 ing, the amplitude of normal motion is inversely 

 as the distance from the origin. The laws of 

 transverse motion are practically the same with 

 those of normal motion, but less pronounced. 

 Near to an origin, the amplitude of the transverse 

 motion is less, but the period greater, than that of 

 the normal motion. The velocity of transmission 

 obtained varies from two hundred to six hundred 

 feet, which is much less than the velocities ob- 

 tained by Mallet and by Abbott. 



— Uhler's check-list of the Hemiptera heter- 

 optera, or true bugs, of North America, recently 

 published, contains 1,448 species, distributed among 

 425 genera, or an average of 3.6 species to each 

 genus. Classification here, as in some other 

 branches of entomology, appears to have been 

 carried too far, though doubtless many more 

 species yet remain to be discovered. 



— Drs. D. E. Salmon and T. B. Smith have just 

 published fProc. biol. soc. of Washington, vol. iii.) 

 a remarkable discovery, made by them, of a new 

 method of producing immunity from contagious 

 diseases. By experimenting upon pigeons, they 

 were able to establish an immunity from the dis- 

 ease known as swine-plague, by the inoculation of 

 solutions in which the pathogenic bacteria had 

 teen cultivated, and afterwards destroyed by heat. 

 The conclusions they reach are as follows: 1°. 

 Immunity is the result of the exposure of the 

 bioplasm of the animal body to the chemical 



products of the growth of the specific microbes 

 which constitute the virus of contagious fevers ; 

 2°. These particular chemical products are pro- 

 duced by the growth of the microbes in suitable 

 culture-liquids in the laboratory, as well as in the 

 liquids and tissues of the body ; 3°. Immunity 

 may be produced by introducing into the animal 

 body such chemical products as have been pro- 

 duced in the laboratory. 



— Professor Davidson, in a paper on the temper- 

 ature of the water of Golden Gate, in Bulletin No. 

 4 of the California academy of sciences, states, 

 that, from a mean of nearly ten years' observa- 

 tions, the lowest temperature is for the month of 

 January, 50°. 49 F. ; and the highest for the month 

 of September, 59°. 68 F. The average range is 

 thus only nine degrees, and the extreme range has 

 only been thirteen degrees. The temperature of 

 the air follows closely that of the water ; and it is 

 the uniformity of the latters temperature along 

 the Pacific coast, and its coldness, which con- 

 spire with the north-west winds of summer to 

 cause the peculiar foggy conditions which prevail. 



— In the Proceedings of the Linnean society of 

 New South Wales, Dr. Lendenfeld reports upon 

 a sponge destructive to oyster-culture. Large 

 areas of oyster-beds in the Clarence River were 

 destroyed by their attaching themselves to the 

 shells, preventing the formation of spat. With 

 the destruction of the beds the sponge disappeared. 

 The latter he describes under the name Chalinula 

 Coxii. 



— Examination of the cheese, which some time 

 ago caused the sudden and severe illness of several 

 hundred persons in Michigan, has shown the 

 poisonous character to be due to a peculiar crystal- 

 lizable substance, or ptomaine, of an intensely 

 cheesy odor, to which the discoverer, Dr. V. C. 

 Vaughan, has given the name of 4 Tyrotoxicon ' 

 (Zeitschr. f. physiol. chemie, x. 146, 1886). 



— Dr. Ten Kate, the anthropologist, has been 

 pursuing his investigations in Dutch and British 

 Guiana, and intends to extend them into Vene- 

 zuela and Florida, chiefly with reference to the 

 Carib Indians. He has already measured, in a 

 very detailed manner, one hundred and six in- 

 dividuals of the Arrowak and other tribes, wood 

 negroes and metis. 



— Major Powell has submitted to the commis- 

 sion investigating the question of the proposed 

 consolidation of the various scientific bureaus his 

 reply to the recent strictures of Professor Agassiz 

 upon the work of the geological survey. The let- 

 ters have not yet been made public, and are to be 

 printed in connection with the testimony taken 



