278 



NATURE 



\yan. 23, 1890 



summit was some 200 or 300 yards southward of the 

 present highest cliff, and that the shallow bank stretching 

 to the south represents the original extension of the 

 island. 



As far as can be judged from Mr. Tufnell's sketch from 

 the north-west and that of the Egeria from the south- 

 south-east, considerable changes have taken place in two 

 years, the different summits shown in the former having 

 disappeared as the sea has eaten away the cliffs. 



The flat to the north seems to be partly due to redis- 

 tribution under the lee of the island of the material 

 removed from the southern face. It is crossed by curved 

 ridges from 3 to 12 feet high, which Commander Oldham 

 considers to have been formed as high beaches during 

 spring tides and strong winds, the flat ground between 

 them, almost at the level of the water, being deposited 

 under normal conditions of weather. 



The island is thus gaining on one side, while losing on 

 the other, but when the high part has gone, this partial 

 recovery will probably cease. 



A little steam issuing from cracks in the southern cliffs 

 was the sole sign of activity, but a pool of water at a 

 temperature of from 91° to 113° F., water which rose in a 

 hole dug in the flat of a temperature of 128° F., and a 

 temperature of 100° F. in a hole dug half-way up the slope, 

 also show that the island still retains heat near the sur- 

 face. The water is sea-water that has filtered through the 

 loose ashes, and it rose and fell with the tide. 



It appears by the condition of the flat that the island 

 has neither risen nor subsided during the past two or 

 three years. 



It will be interesting to watch the ultimate fate of this 

 last addition to the Pacific isles, but it seems probable 

 that its existence as an island will be short unless a hard 

 core is yet revealed. 



The soundings between Falcon Island and Namuka 

 show that they are separated by a valley 6000 feet deep. 



Metis Island, 73 miles north-north-east of Falcon 

 Island, is another volcanic cone that appeared a few 

 years before the latter, but has not yet been examined. 



W. J. L. Wharton. 



WEATHER FORECASTING. 



■pOPULAR interest in weather prediction shows no 

 -^ sign of abating. The January number of the Kew 

 Bulletin is devoted to an account of Herr Nowack's so- 

 called "weather plant," and its failure as an indicator 

 either of coming weather or of earthquakes. Very 

 recently a lively correspondence has been carried on in 

 the daily press on the merits or demerits of the forecasts 

 issued by the Meteorological Office. Accordingly, some 

 remarks on the subject in the columns of Nature may 

 not be out of place. 



One critic says that the forecasts are little better than 

 haphazard guesses, and that the money devoted to them 

 would be better spent on an additional lifeboat or two 

 on the coast. Another says the forecasts are not worth 

 the paper they are printed on, and wishes that the Office 

 published in the newspapers fuller accounts of the weather 

 reported from the coasts. 



The fact is that the Office is compelled by public 

 opinion to issue forecasts. The public will have its 

 forecasts, as in 1867 it would have its storm-warnings, 

 notwithstanding the reluctance of meteorologists to issue 

 either the one twenty years ago or the other at present. 

 It can hardly be doubted that, for these islands at least, 

 conscientious meteorologists would be disposed to agree 

 with Arago, who said in 1846, and printed it in italics 

 in the Annuaire du Bureau des Longitudes: "Jamais, 

 quels que puissent etre les progres des sciences, les 

 savants de bonne foi et soucieux de leur reputation ne se 

 hasarderont k prddire le temps." We are, of course, 



speaking of forecasts based on telegraphic reports, and 

 emanating from a central office. In every country, with- 

 out exception, where forecasts for distant counties or 

 provinces are issued from headquarters, the complaints 

 from outlying stations, of occasional failure, are frequent 

 enough. 



The fact is that at individual stations the percentage 

 of success may be highly satisfactory, as at Mr. C. E. 

 Peek's observatory at Rousdon, Lyme Regis. The 

 results for this point appeared in the Times of January 

 14, and are as follows : — 



00 o ^ 3 45 67 



1884 ... 587 ... 690 ... 20"0 ... ii'o ... 73*4 ... i6*9 ... 9*7 



1885 .., 7o'o ... 8o'o ... i2*o ... 8*o ... 8o'o ... 12*0 ... 8'o 



1886 ... 73'o ... 800 ... ii-o ... 9-0 ... 85-0 ... 8*o ... 70 



1887 ... 75-0 ... 83-0 ... 9-0 ... 8-0 ... 82-0 ... ii-o ... 7*o 



1888 ... 8i*o ... 89-0 ... 5-0 ... 6'o ... 89*0 ... 7'o ... 4"o 



In this, Col. I is percentage of reliable wind and weather. 



Col. 2 ,, ,, wind only. 



Col. 3 ,, wind doubtful. 



Col. 4 ,, wind unreliable. 



Col. 5 ,, reliable weather. 



Col. 6 ,, weather doubtful. 



Col. 7 ,, ,, unreliable. 



On the other hand, at other points the forecasts may 

 be frequently unsuccessful. 



In one important particular not only our own Office, 

 but all other Offices in Europe, signally fail, and that is 

 the quantitative prediction of rain. No one is able, ap- 

 parently, to predict whether the amount of rainfall on 

 the morrow will be a tenth of an inch or a couple of 

 inches. No sudden floods have ever yet been foretold. 

 By this we are not speaking of predicting the approach 

 of floods to the lower valleys from rain which has already 

 fallen on the upper reaches of a river, for that is not 

 meteorological prediction at all. 



With the necessarily incomplete character of the in- 

 formation reaching head-quarters, the wonder is that the 

 Office can attain such success as it does. The main 

 deficiency in the information is in its quantity, and this 

 seems to lie at the door of the Postal Telegraph Office,, 

 which insists on being paid for its telegrams. If meteoro- 

 logical messages were transmitted gratis, we might expect 

 to hear at frequent intervals from our outposts, instead 

 of twice, or, at most, thrice in the twenty-four hours : in 

 fact, from several stations we can only hear once, the 

 cost of more telegrams being prohibitive. It is self- 

 evident that such an amount of information is quite in- 

 sufficient. The weather will not abstain from changing 

 because the hour for a telegraphic report has not arrived. 



The information contained in the telegrams is also 

 deficient in quantity, for the reporters cannot, within the 

 prescribed form of their messages, communicate all the 

 impressions which the ever- varying appearance of the 

 sky may have conveyed to their minds. A skilled cloud 

 observer, who has leisure to practise his powers, is often 

 able to form a very correct idea of what is coming for 

 the region bounded by his own horizon, but he is quite 

 unable to give the benefit of his observations and experi- 

 ence to a friend in another county by telegraphing the 

 information. 



The greatest want which the Office finds in its observers 

 is skill in cloud observation, and it appears to be the case 

 that a cloud observer nascitur non Jit, and that it is next 

 to impossible to teach the art to a new hand, at least by 

 correspondence. 



Instrumental records of the phenomena taking place in 

 the higher strata of the atmosphere are of course unat- 

 tainable, and it is only by carefully watching the upper 

 clouds that we can gain any notion of changes taking 

 place up there, but, by means of such watching, Mr, 

 Clement Ley is able to predict with nearly perfect 

 certainty the weather for the Midlands— his own neigh- 

 bourhood. 



