440 



SCIENCE, 



[Vol. IV., No. 92. 



ries, to the south of Newfoundland, between Porto 

 Rico and the Bermudas, and to the right of the Isle 

 of Marten- Vaz. 



The great depths of the Pacific are differently dis- 

 tributed. Between Japan and California, between 

 40° and 50° north latitude, there is the Tuscarora 

 depression, which has depths of from 6,000 to 8,000 

 metres. Parallel to Japan and the Kuriles there is 

 a depression in which has been found the greatest 

 known depth, — 8,513 metres. 



We see, therefore, that any new great submarine 

 line, having to extend into another zone than that 

 which has received the present Atlantic cables, must 

 traverse depressions in which the bottom reaches a 

 maximum depth of 4,000 metres. The possibility of 

 raising a damaged cable would be very problematical 

 under such conditions, and it would become certainly 

 impossible in case of a cable from San Francisco to 

 Japan. 



Under these conditions, we are forced to conclude 

 that the use of the present cables limits strikingly 

 the progress of submarine telegraphy, which must 

 remain confined to certain zones of the Atlantic, to 

 inland seas, and to lines along the coasts. But if we 

 consider the daily progress of applied science, and 

 the constantly increasing demand for rapid com- 

 munication between nations, it is certain that we 

 must shortly undertake the study of new cables in- 

 tended to traverse the greatest depths of the ocean 

 for long distances. Necessity, therefore, compels us 

 to investigate the new solutions of the problem, 

 which may furnish us with light cables, easy to lay, 

 and possible to repair. 



A cable made by Mr. J. Richard-! is composed as 

 follows: core of silicium bronze equal in weight to 

 that of the ' Pouyer-Quertier ' cable, or, per nautical 

 mile, 220 kilos. ; gutta-percha, 180 kilos. ; layer of 

 hemp, 80 kilos. The sheathing is formed of 28 wires 

 of galvanized iron of 1.25 millimetres in diameter, 

 each covered with hemp, and all twisted into a rope 

 around the dielectric; the wires, 500 kilos. ; the hemp 

 covering them, 250 kilos. The weight of the cable 

 is, therefore, 1,230 kilos, in the air, and 320 kilos, in 

 the water. Its diameter is 25 centimetres, and its 

 resistance to fracture, 2,800 kilos., of which the core 

 supports one-half. Under these conditions, the cable 

 can support from eight to nine nautical miles of its 

 length, and can be raised from the greatest depths. 

 The results of this comparative examination are self- 

 evident. 



For an equal conductivity and an approximately 

 equal mechanical strength, the new cable is in weight 

 and bulk equal to about two-thirds of the Pouyer- 

 Quertier cable. It would cost about $165 less per 

 mile, and would require, for laying, a ship and engines 

 of less power, and therefore cheaper. The reduced 

 armature will suffice to resist friction and the attacks 

 of animal life in the deep sea; but for the shore ends 

 we must keep to the types generally employed. Such 

 as it is, and although it may undergo modifications 

 in detail from a more complete study and from ex- 

 perience, it merits the attention of competent engi- 

 neers. 



THE AMERICAN PUBLIC HEALTH 

 ASSOCIATION. 



The twelfth annual meeting of this association, 

 held at St. Louis from Oct. 14 to Oct. 17, was one 

 of the most successful in the series. The number 

 of members present was large; and it is a matter of 

 great promise for the association, that state and mu- 

 nicipal boards of health were more fully represented 

 than at any previous meeting. 



These occasions have a value far beyond the intrin- 

 sic merit of the papers presented. The discussions 

 are always instructive, often valuable. The sanitary 

 questions of municipal life vary essentially in the 

 different cities of the Union, and are answered in as 

 many ways; and every public-health officer will find 

 something to learn, as well as instruction to give. 



Several threadbare topics, which have occupied the 

 attention of this body for years, have disappeared 

 from the programme, such as vaccination, yellow- 

 fever, and malaria. 



The order of exercises, as arranged by the exec- 

 utive committee, included the following subjects : 

 Hygiene of occupations, Hygiene of the habitations 

 of the poor, School hygiene, Adulteration of food, 

 Water-pollution, Disposal of sewage by chemical 

 action or irrigation, The observable effects upon the 

 public health of official sanitary supervision, The 

 work of state and municipal boards of health, Dis- 

 ease-germs, Cremation as a sanitary measure in times 

 of great epidemics, Survey of present sanitary situ- 

 ation in St. Louis. 



Nearly forty papers upon these topics were sub- 

 mitted. By far the larger number were of more than 

 average merit, giving rise to interesting and instruc- 

 tive debate. The following-named papers contained 

 more, perhaps, than the others upon the newer sub- 

 jects in sanitary work. 



Dr. Sternberg's paper upon disease-germs, read 

 at the evening meeting of the third day, attracted 

 the largest audience of the convention. This paper, 

 which was illustrated by a collection of remarkably 

 good microphotographs projected upon a screen, 

 was substantially a re-statement of observations 

 already made, and fortified by additional research. 

 His statement that he was still at work upon the 

 study of yellow-fever, by means of an abundant ma- 

 terial furnished him from Havana, is a source of 

 much satisfaction, somewhat diminished by the fact 

 that this indefatigable and competent investigator 

 carries on his work at his own expense. How long 

 will the people of this country be willing to accept 

 from the well-appointed laboratories of the old world 

 the researches of Koch, Pasteur, and Klein, — in- 

 vestigations into diseases of as much importance to 

 one side of the Atlantic as to the other, — and still 

 hesitate to properly study the one disease peculiar to 

 our own continent — yellow-fever? 



Dr. Sternberg's assertion that he has demonstrated 

 the non-existence of a yellow-fever germ in the blood 

 cannot be strictly accurate. At this day one cannot 

 exclude the possibility of making visible, by some at 

 present unknown methods, organisms not yet recog- 



