134 ANNUAL OF SCIENTIFIC DISCOVERY. 







of what is called the atmospheric wave, which means an ideal sur- 

 face in the ^atmosphere at which the pressure is everywhere the same. 

 If the atmosphere were still and undisturbed, this would be parallel 

 to the earth's surface, and would never vary. Such, however, is by 

 no means the case, the variation being sometimes enormous, rapid, 

 and incessant, and strictly marking the conditions of calm and storm 

 in the parts of the earth over which the wave is traced. One of the 

 best illustrations of the action of this wave was afforded in the great 

 storm which seriously injured the English and French fleets in the 

 Black Sea on the fourteenth of November, 1854. This was by no 

 means a local storm, as was proved by the comparison of more than 

 two hundred and fifty reports from observers scattered all over the 

 continent. 



On the twelfth of November, 1854, the pressure of the air, which 

 had been low, was enormously high on the line ranging from the west 

 of England into France, reaching almost to the Pyrenees, but at vari- 

 ous places east of this line the barometer was low. A great undula- 

 tion of the air was taking place, and the ridge of a commencing 

 wave was in the line here stated. As yet the storm had not com- 

 menced ; but before four-and-twenty hours had elapsed this vast 

 wave had moved toward the east, the north part of the crest having 

 then reached Sweden, while the southern part had advanced far in 

 the Mediterranean. It went through the great cities of Berlin, Dres- 

 den, and the southern part, and, having the Alps as its boundary, was 

 lost in their windings. On each side of this crest the indications of 

 storm were very marked. 



Still another day elapsed, and the wave had now reached St. Pe- 

 tersburg and Dantzig, while its southern part was close to Vienna, 

 and had entered the Adriatic, running down the coast of Dalmatia. 

 On the fifteenth it was on the Carpathian Mountains, and on the six- 

 teenth the crest had reached the Black Sea. Beyond that, there 



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were no observatories to mark its progress. The storm took place 

 when the low advancing wave glided over the gloomy waters of the 

 Black Sea, long before the crest made its appearance. The weather 

 is described as having been favorable enough until the fatal atmos- 

 pheric wave bore down on the spot. Then, indeed, the barometer fell 

 rapidly ; but it was too late. 



The high crest so curiously indicated could not be unaccompanied 

 by depression. It commenced and was traceable at a great distance, 

 and, in point of fact, the depression everywhere preceded the ad- 

 vancing wave, while another less considerable followed it. But while 

 at the beginning the difference was small and the result unimportant, 

 in proportion as the wave advanced toward the east, the hollow in 

 advance, became greatly deepened, or, in other words, the mercury 

 stood very low indeed. The strength of the storm was felt where 

 the depression reached its minimum, in the Black Sea, on the four- 

 teenth of November. At that time the depression had been suc- 

 ceeded by the crest of the wave between St. Petersburg and the 

 Dalmatian coast. The course of this storm, from its first commence- 

 ment on the shores of the Atlantic till it reached the Black Sea, and 

 the rate at which it was travelling, were matters perfectly within cal- 

 culation after it had passed over the British Islands, and the time of 



