112 



NATURE 



[November 30, 1899 



international commercial intercourse will become precise only 

 when we adopt Greenwich dates and Greenwich time throughout 

 the world. This improvement, conducing as it does to the 

 transaction of daily business, will not injure but rather be help- 

 ful to meteorology. No one has ever attempted to plot upon an 

 ocean chart the observations of a storm by a hundred vessels at 

 sea, but has found inextricable difficulty with records that are 

 kept by the rules of the ancient navigators ; the trouble is with 

 the date of the month and day of the week. The modern navi- 

 gator and the modern business man will do well to think, speak, 

 and write of Greenwich days and dates only, if he would attain 

 precision in current history," 



The West Indian hurricane of August 7-14 is described by 

 Prof. E. B. Garriott in the National Geographic Magazine, 

 from which the accompanying diagram of the storm has been 

 reproduced. During August 7 and 8 the character and extent 

 of the destruction caused in the Leeward Islands, Porto Rico, 

 and Santo Domingo were such as will make the hurricane rank 

 among the historical storms of the West Indies. At San Juan, 

 in Porto Rico, the barometer began to fall at 10 p.m. on 

 August 7, and the lowest recorded reading, 29-23 inches, was 



The West Indian Hurricane. 



reached at 8'30a.m. on August 8. The hurricane was strongest 

 at San Juan between 7 and 9 a.m. on August 8, when the wind 

 velocity was calculated by a U.S. Weather Bureau observer at 

 85 to 90 miles an hour. The rainfall was very heavy, a total 

 of 6-37 inches falling, of which 4-18 inches fell from noon to 

 8 p.m. on August 8. By prompt action the U.S. Weather 

 Bureau were able to warn many places of the approach of the 

 hurricane centre. Prof. Garriott states that the warnings out- 

 ran the storm by a period which varied from a few hours at the 

 easternmost Leeward Islands to thirty-six and forty-eight hours 

 at points along the South Atlantic coast and gulf parts of the 

 United States. 



The pilot chart of the North Atlantic ocean for November 

 contains a very useful map of the hurricane tracks during the 

 ten-year period, 1890-99, and the distance travelled by each 

 storm centre during twenty-four hours. With a few exceptions 

 the tracks exhibit the usual features, the motion of the centre in 

 that portion of the track to the southward of latitude 25° being 

 directed towards a point between north and west, and thence 

 moving in a north-easterly direction. The position of this point 

 of recurvature or point of greatest westing is arranged in a 

 NO. 1570, VOL. 61] 



tabular form. From this table it is evident that to rely rrpor> 

 the assertion that the storms of a particular month in the West 

 Indies recurve within certain fixed and narrow limits of latitude 

 may lead to serious error at a most critical time. Thus the 

 hurricanes of September, instead of recurving between 27° and 

 29°, as formerly maintained, may recurve in any latitude from 

 20° 20' to 33° 30' north. Likewise those of October, instead of 

 recurving in latitude 20°— 23° north, may continue their north- 

 westerly course until the parallel of 39° is attained. 



The Deutsche Seewarte has published in a quarto volume the 

 results of meteorological observations made on board German 

 ships for the ten- degree square of the North Atlantic comprised 

 between latitude 20°-3o° N. and longitude 6o°--jo° W. This is 

 the seventeenth square, for which the observations have been 

 similarly discussed and published, in the district of the North 

 Atlantic lying between latitude 20° and 50° N., leaving but a 

 small area to complete this very valuable work. It joins on to- 

 the nine ten-degree squares lying between latitude 20° N. and 

 10'' S. and longitude 10° to 40° W. discussed and published some 

 time ago by the Meteorological Council, so that shipmasters- 

 navigating that part of the ocean have at their disposal a large 

 amount of trustworthy information extending over a considerable 

 number of years. The observations are given in a tabular form 

 for each month, and, for each one-degree square, and the results 

 are then combined for each five-degree square. They show the 

 distribution of winds under 16 points of the compass, the 

 prevalence of storms, the mean barometric pressure, air and sea 

 temperature, duration of rainfall and other useful data, and the 

 form adopted allows of the results of future years, or of those 

 obtained by other countries, being added ; so that, if desired, 

 comprehensive charts, from accumulated materials, could be 

 constructed without going through the preparatory work de 



Two or three months ago reports were published in the 

 daily press of the discovery of an electrical method of giving 

 sight to the blind. It was alleged that Mr. Stiens had suc- 

 ceeded in constructing an electrical apparatus which performed 

 all the functions of the eye and was an efficient substitute for it. 

 Like many other newspaper reports of so-called scientific dis- 

 coveries, this has proved to be without sound foundation. Mr. 

 G. H. Robertson, who is himself afflicted with blindness, 

 describes in the Electrician the results of personal inquiries into 

 the matter with a member of the staff of our contemporary. 

 In spite of several visits to Mr. Stiens, no experimental proof 

 in substantiation of the claims which were put forward on his 

 behalf was obtained, and the conclusion arrived at is that these 

 claims are foundless. Life is so short and crowded with so- 

 many important duties that it is impossible to investigate the 

 many sensational statements made by irresponsible interviewers,, 

 but we are grateful to any one who will take the trouble to 

 examine some of the rumours which are put forward in the 

 name of science. 



In the Bulletin of the French Physical Society, No. 137, is 

 described an ingenious disposition for estimating the duration of 

 Kerr's phenomenon, in which certain dielectric liquids are made 

 to assume the optical properties of double refracting crystals by 

 placing them between the plates of a condenser. The light 

 observed is produced by the spark by which the condenser is 

 discharged, and the time interval between the discharge and the 

 passage of the light through the condenser may be varied by an 

 arrangement of mirrors, whereby the rays may be made to 

 traverse any length of path required. The experimenters, MM. 

 Abraham and Lemoine, find from these investigations that Kerr's 

 phenomenon is reduced to half its original value in the four- 

 hundred-millionth of a second, and becomes insensible in the 



