1172 



METEOROLOGY. 



[nrzBov's FORECASTS, ETC. 



bought touch each other, will come into leal at 

 different Jutes. In no troo ii thU more strikingly ex- 

 hibited than in the beech : two beeches growing close 

 together may be seen to vary a couple of weeks in their 

 period of coming into loaf. The age of the treo also 

 causes a difference to occur. In the different kinds of 

 lilac* and laburnums, there will be a range of some day* 



in their time of coming into bloom. Amongst herbaceous 

 plants, none that have been transplanted should be the 

 objects of record. Respecting the observations on the 

 ripening of fruits, the strawberry will serve as an ex- 

 ample : the variety called Black Prince will be ripe 

 before Kean's seedling ; Kean's seedling before British 

 Queen ; and British Queen before the Elton Pine. 



CHAPTER V. 

 WEATHER-FORECASTS BALLOON OBSERVATIONS CLIMATOLOGY, ETC. 



[THIS Chapter baa been added by the Editor, as in part supplementary to subjects already treated on, and also to 

 afford information on various matters, pertaining to Meteorology, which have not hitherto been noticed. Amongst 

 such are Admiral Fitzro/s Weather-Forecasts ; Polar and Equatorial Currents ; Cyclones ; Rules for predicting 

 tlie Weather ; Animal Instincts ; Free Electricity, and its Phenomena ; Mr. Glaishers Balloon Ascents ; Shooting- 

 Stars and the Aurora ; Meteorological influence of Drainage ; Ozone ; Determination of Heights ; Weather 

 Registration ; Gaseous Radiation ; Snow-line ; Distribution of Heat ; Rainfall ; Plants and Animals as affected 

 by Climate ; Meteorology and Ethnology ; Endemic and Epidemic Diseases ; Tables of Mean Temperature, <kc. J 



IK the preceding pages, the student, or general reader, 

 will find an ample disquisition on the laws of Meteoro- 

 logical Phenomena, and some useful advice and aid, 

 should he be desirous of pursuing the subject practically. 

 Within the last few years, an idea has prevailed in scien- 

 tific circles, that it is possible to predict the probable 

 kind of weather which may occur within certain limita- 

 tions. Such an object is of the highest importance to us 

 as a seafaring nation, losing, as we do, annually, an im- 

 mense sum by the wreck of vessels near our coasts. 

 The Meteorological Department of the Board of Trade is 

 devoted to obtaining observations, and in generalising 

 them, with the hope that the laws governing excessive 

 changes of the weather may thus be discovered. To 

 Admiral Fitzroy we are indebted for a great amount of 

 untiring exertion and unequivocal success. Under his 

 direction, telegrams are daily forwarded to all our 

 ports, intimating the weather which may be expected 

 to occur ; and a system of signals has been arranged, by 

 which vessels, near our coasts, can be warned of an im- 

 pending storm. 



Wu present our readers with the following epitome of 

 the results arrived at by Admiral Fitzroy, and the prin- 

 ciple on which he proceeds ; and are indebted to the 

 pages of the Athciuxum for the resume. The remarks 

 are founded on a Report which was furnished by the 

 admiral, during the summer of 18C2 : 



"The Report is highly valuable, for it contains the 

 first-fruits of the measures taken by government to 

 utilise our knowledge of meteorology, with reference 

 more particularly to storm telegraphy. The system at 

 present in use was organised in 1857 ; when it was 

 arranged that simultaneous observations should be made 

 daily at various localities in the British Islands, also in 

 and around the Atlantic, and at stations on the Euro- 

 pean continental coasts. By combining these observa- 

 tions in synchronous charts and otherwise, it was dis- 

 covered, that though the weather and wind appeared to be 

 quite irregular, yet that there was much uniformity and 

 similarity of character in successive variations. It was 

 further ascertained, that by means of a comparatively 

 small number of observations made daily at a few 

 elected stations sufficiently far apart, and by the use of 

 a self-registering barometer at a central station to which 

 meteorological telegrams are sent from the outlying sta- 

 tionsdistinct intimation of marked changes of weather, 

 and warning of dangerous storms, might be communicated 

 to the centre, and from thence to all other points of any 

 telegraphic combination. 



1 10 yean were spent in bringing the system to 

 working order ; and on the 6th of February, 1861, the 

 first warning* of portending storms were given. The 

 value of this notice was particularly marked by the cir- 

 cnnutanoe that a fleet of vessels became disabled or 

 wrecked on the 8th or 9th, which were lying off Shields, 

 and whoM captain* disregarded the timely warning. 



The misfortune was, however, a singularly pertinent 

 example of the truth of the homely proverb, that ' it is 

 an ill wind that blows no one good ;' for since that event, 

 Admiral Fitzroy states that, ' whether from having ap- 

 preciated these storm signals, or from other reasons, the 

 fact is, that very few wrecks occurred on our coasts dur- 

 ing the notoriously tempestuous weather of February and 

 March, 1801 ; and comparatively few since.' 



" It is gratifying to find that the aid afforded by the 

 government offices is not confined to British ships, and 

 that a considerable demand for the publications emanat- 

 ing from Admiral Fitzroy's department, has been made 

 by foreign nations. It lias been truly observed, that one 

 of the greatest evils of meteorology, hitherto, has been the 

 practice of incessantly making observations without any 

 very definite objects in view, with the vague hope that 

 eventually they may become of value. The aim of the 

 Government Meteorological Department is to correct this 

 evil, by not only instituting observations of a strictly 

 scientific nature, made with scientific instruments, but 

 also in turning the observations to practical account. 



"Admiral Fitzroy considers that the phenomena ac- 

 companying storms are now so readily explicable by the 

 light thrown upon them by Dove's theory of polar and 

 equatorial currents, which has been translated and pub- 

 lished by the Board of Trade, and they are so marked by 

 barometers, that it is quite inexcusable to undervalue 

 their warnings. The principal phenomena connected with 

 storms may be thus summed up. Great and important 

 changes of weather and wind are preceded, as weft as ac- 

 companied, by notable alterations in the state of the 

 atmosphere ; approaching storms are usually shown by 

 falls in the barometer exceeding one inch, and by differ- 

 ences of temperature exceeding about fifteen degrees. A 

 tenth of an inch an hour, is a fall indicating a storm or 

 very heavy rain. The more rapidly such changes occur, 

 the more risk there is of dangerous atmospheric commo- 

 tion. These circumstances show the necessity of fre- 

 quently observing the barometer, and the advantages of 

 a self-registering instrument. 



"As all barometers often, if not usually, show what 

 may be expected a day, or even days, in advance, rather 

 than the weather of the present or next few hours, and 

 as wind or its direction affects them much more than 

 rain or snow, duo allowance should always be made for 

 days as well as for hours to come. Admiral Fitzroy re- 

 commends that the following table of iivi-nyo tempera- 

 tures between 8 and 9 o'clock A.M., near London, should 

 be used to assist in foretelling the direction and nature 

 of coming wind and weather : 



January 

 February 

 March . 

 April 

 May . 

 June . 



37 

 39 

 41 

 40 

 53 

 09 



July . 



August . 



September 



October 



November 



December 



C2 



Cl 



57 



50 



43 



