PROGRESS OF METEOROLOGY IN 1889. 211 



of equal barometric pressure (or more correctly of equal departures from 

 the normal) together with wind directions, temperatures, and weather. 



The suggestiou of this method of representing barometric observa- 

 tions was made by Brandes in 1810 in recommending that observers 

 should give in their record books the departure from the normal of 

 every barometric observatiou, and that these departures should form 

 the principal data in the study of the compiled data. Whether Pro- 

 fessor Loomis was acquainted with this suggestion, does not appear. 

 This graphical method is now the essence of the modern weather map, 

 and the memoir of 1843 in which the method was presented created a 

 protbund impression. In his appreciative biographical sketch. Pro- 

 fessor iSTewton expresses his opinion that the introduction of this single 

 method of representing and discussing the phenomena of a storm was 

 the greatest of the services which Professor Loomis rendered to science. 

 Professor Loomis's own estimate of the method at the time of publica- 

 tion was expressed as follows: "It appears to me that if the course of 

 investigation adopted with respect to the two storms of February, 1842, 

 was systematically pursued we should soon have some settled princi- 

 l)les in meteorology. If we could be furnished with two meteorological 

 charts of the United States daily for one year it would settle forever the 

 laws of storms. No false theory could stand agaiust such an array of 

 testimony. Such a set of maps would be worth more than all which has 

 hitlierto been done in meteorology. A well arranged system of observa- 

 tions spread over the country would accomplish more in one year than 

 observations at a few insulated posts, however accurate aud complete, 

 continued to the end of time. Is not such an enterprise worthy of the 

 American Philosophical Society? If private zeal could be more gener- 

 ally enlisted the war might soon be ended, and men would cease to 

 ridicule the idea of our being able to predict an approaching storm." 



Thirty years passed before the system of observations was inaugurated 

 and the maps constructed for which Professor Loomis here appealed. 

 In 1871 the signal service was established, and as soon as two years' uiaps 

 had been issued. Professor Loomis turned again, with unabated inter- 

 est and enthusiasm, to the work that he began with such scanty mate- 

 rial in 1840. For the remaining tifteen years of iiis life he devoted 

 nearly his whole strength to this work. Twenty-three papers, entitled 

 Contributions to Meteorology, were published in the American Journal 

 of Science, and in 1884 he began a revision of the whole series. This 

 revision was arranged in three chapters, covering areas of low pressure, 

 areas of high pressure, and rain-fall. Chapters i and ii were presented 

 to the National Academy in 1885 and 1887, respectively, and chapter in 

 was completed and issued a few weeks before the author's death. In 

 these three monographs is compiled a wealth of statistical data which 

 will long afford the observational basis for the explanation of climate 

 and for the theoretical study of the atmospheric circulation and the 

 phenomena of storms. 



