November 24, 1898] 



NATURE 



The Engineering and Mining [ournal announces that Dr. 

 Napier Ford has invented a substitute for rubber, namely per- 

 choid, which is described as an oil that has undergone a high 

 degree of oxidation. The oil is heated with litharge, stirred 

 long and continuously, and then allowed to cool. Specially 

 prepared tow is then dipped into it and placed in wire baskets, 

 and exposed to air. The oil admitted to the filaments of the 

 tow thus becomes wholly oxidised. This is drawn through 

 rollers, and comes out a leathery material closely allied to, if 

 not identical with, rubber. Its tenacity is increased by mixing 

 sulphur with it. It is said that perchoid can be rolled as thin 

 as a piece of tissue-paper, and that it makes leather impervious 

 to moisture, though not to air. 



Some ten years ago a French missionary started the systematic 

 rearing of two kinds of spiders for their web, and the Board of 

 Trade Journal states that a spider web factory is now in suc- 

 cessful operation at Chalais-Meudon, near Paris, where ropes 

 are made of spider web intended for balloons for the French 

 military aeronautic section. The spiders are arranged in groups 

 of twelve above a reel, upon which the threads are wound. It 

 ■s by no means easy work for the spiders, for they are not re- 

 leased until they have furnished from 30 to 40 yards of thread 

 each. The web is washed, and thus freed of the outer reddish 

 and sticky cover. Eight of the washed threads are then taken 

 together, and of this, rather strong yarn cords are woven, which 

 are stronger and much lighter than cords of silk of the same 

 thickness. These spider web ropes are very much more expen- 

 sive than silk ones, but it is hoped to reduce their cost somewhat 

 in the future. 



At the meeting of the Academy of Science of St. Louis on 

 November 7, Mr. James A. Seddon, of the Missouri River 

 Commission, presented a paper on resistance to flow in 

 hydraulics, in which the point was made that relatively a small 

 part of this resistance, so far as open streams were concerned, 

 was directly attributable to friction against the bottom and 

 limiting banks, but that the resistance was found acting between 

 accelerations and impacts, and showed in forced distortions of 

 the free surface, from which forms the energy passed into 

 internal motion. 



We learn from Science that the State Legislature of Vermont 

 has passed an Act providing for the equipment and maintenance 

 of a State laboratory, which shall include in its work "the 

 chemical and bacteriological examination of water-supplies, milk 

 and all food-products, and the examination of cases, and 

 suspected cases, of diphtheria, typhoid fever, tuberculosis, 

 malaria, and other infectious and contagious diseases.'' The 

 sum of 1000/. has been granted for the establishment of the 

 laboratory, and 1600/. per year voted for current expenses. 

 Dr. J. H. Linsley is director of the laboratory. It appears that 

 only three States have established similar laboratories — 

 Michigan, Massachusetts and New York. 



We have received from Prof B. Sresnevsky, director of the 

 louriev (Dorpat) Observatory, the twelfth yearly report upon 

 the rainfall of the Baltic provinces of Esthonia and Livonia. 

 The observations refer to the year 1897, and contain monthly 

 and yearly values, and the number of rainy days, for 125 stations, 

 and the same values are also grouped into districts. Although 

 not stated in the title, the work also contains temperature observ- 

 ations made at 8 a.m., and these are treated in the same way as 

 the rainfall values. The ten-yearly mean of rainfall for the whole 

 district is 2 1 '9 inches, and the average number of rainy days is 

 162. The driest month is January, and the wettest, July. The 

 general mean of the yearly temperature (for S a.m.) is 39°'4 

 (January iS''5, July 62°'2). The results have been prepared by 

 Dr. A. von Oettingen, formerly director of the Dorpat Observ- 

 N). 15 17, VOL. 59] 



atory, and we are glad to see that, as soon as values for fifteen 

 years have been obtained, it is proposed to issue a general 

 summary, with diagrams. 



The Pilot Chart of the North .\tlantic Ocean, published by 

 the Hydrographer of the U.S. Navy for November, gives some 

 interesting details of the track followed by the recent destructive 

 hurricane in the West Indies. The centre of the storm passed 

 to the southward of Barbados at 9h. 30m. p.m. on September 

 10 ; and reached Kingstown, St. Vincent, at noon on the nth. 

 From St. Vincent, the hurricane moved north-westward at the 

 low rate of six miles per hour, and gales were experienced 

 within a radius of 75 miles from its centre. On the 12th and 

 13th it was central to the west of the Lesser Antilles, turning 

 to the northward on the latter date. On the 14th it continued 

 its north-westerly course, recurving to the north-east on the 17th, 

 near latitude 30° N. and longitude 71° W. The British steamship- 

 IrrawadJy, from port of .Spain to New York, encountered the 

 hurricane on the nth, and kept within the storm area until the 

 iSth ; she had strong winds to gales of hurricane force through- 

 out this period. On the l8th and 19th the storm pursued a 

 north-easterly course, moving at the rate of twenty-five to 

 thirty miles an hour, its area being increased considerably. 

 The last report received by the U.S. Office was from the British 

 steamship Hesperia. She reports, latitude 42° N., longitude 

 42' W., on September 20: "Winds S.S.W., force 10, shifting 

 N.W., lowest barometer 29 '62 inches ; sqvialls blowing with 

 terrific force ; sea at times mountainous." The storm seems to- 

 have followed a somewhat more northerly and seaward course 

 than the average track for September, as calculated by Padre 

 Vines in his investigation of the general movements of Westi 

 Indian hurricanes, published by the Weather Bureau of 

 Washington. 



The next volume of the Transactions of the Woolhope Field 

 Club will contain a valuable paper (of which some copies have 

 been printed) on the Hereford earthquake of December 17, 

 1896. The paper is the joint work of Mr. H. Cecil Moore, the 

 Secretary of the Club, Mr. R. Clarke and Mr. A. Watkins, and 

 gives the results of careful inquiries made in the central county 

 of Herefordshire with regard to the damage caused by the 

 earthquake. In the city of Hereford alone, it appears that 218 

 chimneys had to be rebuilt ; but in the parish of Fownhope the 

 damage was relatively greater, for twenty-two chimneys were 

 repaired or rebuilt. The authors remark that a circle of six 

 miles radius, with its centre at the centre of the ancient up- 

 heaval of the Woolhope Valley, includes by far the greatest 

 damage in the county. The paper is illustrated by two plates, 

 one showing the fractures in .several pinnacles of Hereford 

 Cathedral and other churches ; the second being a map of the 

 county, on which are marked the places where buildings were 

 damaged. 



The Geological Survey of England and Wales has lately 

 published short explanations of the new series maps relating to 

 the country around Bognor and Bournemouth, by Mr. Clement 

 Reid. We are now able to call attention to another explanation 

 relating to Eastbourne, by the same author, and printed for 

 H.M. Stationery Office, price dd. It contains a general account 

 of the geology of this favourite residential district, which in- 

 cludes not only Eastbourne, but also Newhaven and Seaford. 

 The strata comprise the Cretaceous rocks from the Weald Clay 

 to the Upper Chalk, the Lower Eocene strata, and superficial 

 Drifts. Illustrations are given of the characteristic fossils. 

 Mr. Reid calls attention to certain disturbances seen on the fore- 

 shore near Beachy Head, and a study of these leads him to con- 

 clude that the Chalk of the South Downs, unlike that of the 

 North Downs, is not connected across the Channel with France. 



