422 



NATURE 



[August 30. 1900 



in which the velocity of the centre after recurvature off the 

 coast of Florida fell to about three miles an hour through three 

 degrees of latitude. 



We have received a copy of the meteorological observations 

 made at Sir Cuthbert Peek's observatory at Rousdon, Devon, 

 for the year 1899, the sixteenth year of the series. This obser- 

 vatory is a second order station of the Royal Meteorological 

 Society, and possesses a very complete equipment of instruments, 

 both astronomical and meteorological, including various patterns 

 of standard anemometers, the observation and comparison of 

 which form a special and valuable feature of the regular work of 

 the station. The mean temperature of the year exceeded the 

 average by more than 2° ; but the year was free from extremes in 

 either direction, although at Greenwich on August 12 a tempera- 

 ture of 90° was recorded. The rainfall was about two and a half 

 inches below the average, and amounted to only 29*31 inches; 

 falls of an inch or more occurred on five days. A daily com- 

 parison is made between the actual weather and the forecasts of 

 the Meteorological Office ; as regards wind, the percentage of 

 success has increased from 69 in 1884 to 93 in 1899, and in 

 the case of weather, from 73 to 92 in the same period. 



The following notes from a report by Mr. H. A. Byatt, 

 assistant collector. Fort Alston, are published with others in the 

 British Central Africa Gazette : — " After passing over the 

 ridge of hills which culminates about two miles to the east of 

 Ndonda, some forty miles from the lake shore, the appearance 

 of the country and the nature of its soil changes very consider- 

 ably. In place of the low-lying marshy expanses along the 

 coast, one finds a monotonous series of undulating grassy plains, 

 covered almost exclusively with a growth of tall rank grass. 

 The soil generally, though occasional small deposits of clay are 

 found, consists of a layer of coarse porous sand, apparently of 

 no great depth, lying upon a substratum of hard rock, and may 

 well have been washed down by centuries of rain from the low 

 hills above mentioned. The country is remarkably waterless. 

 Judging by the appearance of the vegetation which it supports, 

 the soil is of poor quality, and offers but little hope of successful 

 cultivation. Large timber is conspicuous by its absence, and it 

 is only at rare intervals that the raphia-palm and other trees 

 requiring a copious supply of moisture are found ; but possibly 

 such woods as the Mlanje cedar might be introduced with suc- 

 cess. Owing to the rank growth of grass, it is an ideal cattle 

 country ; but the true reason of the excellent condition of cattle 

 in this country is to be found, I believe, in the presence of a 

 certain salt in the earth — possibly a nitrate or phosphate t)f soda. 

 In many places itis so abundant that upon the evaporation of 

 the water it is left as a thick white deposit on the surface of the 

 soil, whence it is gathered up by the natives and used as a con- 

 diment. Of other minerals, beyond the existence of graphite, 

 I have so far found no trace." 



The progress of work on the new wheel-pit of the Niagara 

 Falls Power Company, at Niagara Falls, N.Y., which is in- 

 tended to supplement the present hydraulic installation of the 

 same company, is described and illustrated in the New York 

 Electrical Review (August 15). It is only a few years since the 

 company began operations with a plant capable of being ex- 

 tended to 50,000 horse-power. Both the rapid growth of 

 electrochemical industries at Niagara, and of electric power 

 applications in BuiTalo, twenty-six miles away, have rapidly 

 carried the plant up to the limit of its former hydraulic equip- 

 ment. Now the new one, which is slightly larger than the old, 

 is under construction, and it is expected that within a year 

 105,000 horse-power will be generated and distributed from this 

 one plant. The growth of such industries in the United States 

 has been extraordinary. In New York State there is another 

 plant under construction which will be finished within a year, 

 NO. 1609, VOL. 62] 



and will develop the enormous total of 150,000 horse-power. 

 Practically all of the latter installation will be used in electro- 

 chemical work in the manufacture of carbides and caustic and 

 bleaching powder. 



The manufacture of artificial dye-stuffs in Germany was 

 referred to in a recent report from H.M. late Consul-General 

 at Frankfort-on-Main. The endeavours of manufacturers and 

 industrial chemists are directed, generally speaking, to pro- 

 ducing the organic natural products, such as those of colour 

 plants, dye woods, insects, molluscs, &c., by artificial and even 

 cheaper and purer means, and in a more serviceable form for 

 dyeing ; also to producing new colours, which not only approach 

 in brilliancy and effectiveness the natural kinds, but even surpass 

 them. Since the discovery that the important dye-stuff madder 

 —alizarine— could be produced in an easy and cheaper manner 

 from the carburetted hydrogen of coal-tar, the use of dye-stuffs 

 obtained by coal-tar distilling has gradually grown to such an 

 extent that in Germany about five times as many artificial 

 colours are made as in all other countries combined. According 

 to the census in 1895, there existed twenty-five factories for 

 the manufacture of aniline and aniline colours, and forty-eight 

 factories (with seven branches) for the production of other coal- 

 tar products {i.e. not only for colours, but also for other com- 

 modities, such as picric acid, &c.). The aniline works employ 

 7266 hands, the latter factories 4194 ; in all, 1 1,460 men. 



In connection with the foregoing note, the Board of Trade 

 fournal gwes some particulars as to the n^nufacture of artificial 

 indigo in Germany, from a report to the Foreign Olifice. The 

 importance of indigo is evidenced by the fact that the production 

 of natural vegetable indigo equals in value the entire world's 

 production of artificial dye-stuffs. The present artificial indigo 

 of commerce represents almost pure indigotin. It is sold in the 

 form of a 97 per cent, powder, whereas the indigotin contained 

 in vegetable indigo fluctuates between 70 and 80 per cent. It 

 contains no indigo-red, no indigo-brown and no indigo- blue. 

 The lack of indigo-red and indigo-blue, which both seem to be 

 of some importance in the relation of the dye-stuff to the fibre, 

 are its special disadvantages. The indigo-red seems to be of 

 importance in the production of darker shades of colour. There 

 is no doubt that at some time not too far off it will be possible 

 to produce this ingredient also. Artificial indigo is used by 

 dyers in the same way as vegetable indigo. If it is possible to 

 render the process of manufacture materially cheaper, and thereby 

 to considerably reduce the price of artificial indigo, the danger 

 to natural indigo will be greatly increased ; it is, indeed, to be 

 feared that with the increase of chemical knowledge the same 

 fate awaits this dyeing plant, which is extensively cultivated in 

 British territories, as overtook the Krapp plant, the cultivation 

 of which nowadays no longer pays. Artificial indigo affords a 

 new example of the manner in which applied science revolu- 

 tionises the most varied spheres and destroys as well as creates 

 great wealth. 



The Atlantic Monthly lox August contains an account, by Mr. 

 Sylvester Baxter, of a method devised by Mr. Arthur J. Mundy, 

 whereby a ship may be guided into port in stormy weather 

 which prevents ordinary signals from being of service. The 

 method is called " Acoustical Triangulation," It is based on 

 the property that sound travels under water with a velocity that 

 is unaffected by the disturbances such as winds, which have so 

 large an influence on the propagation of sound-waves in air ; and 

 the putting of this principle into practice depends on the 

 invention of a successful apparatus for ringing a bell underwater 

 by electrical connections. Three bells placed at the corners of 

 a triangle, preferably equilateral, are sounded at known intervals 

 of time. By noting the intervals of time between the instants 

 when the first and second bells are heard, the locus of the ship's 



