Jan. 18, 1877] 



NATURE 



263 



METEOROLOGICAL NOTES 



Storms and Floods of the Past Six Weeks. — An 

 examination of the Daily Weather Maps published in different 

 countries of Europe for this period is very instructive. The 

 most common course taken by the winter storms of nortli-western 

 Europe is an easterly or nortli-easterly one, and the tracks of 

 their centres lie somewhere between Faro and Iceland. Hence 

 the winter climate of the British Isles is characterised by south- 

 westerly winds, and the relatively high temperature and humidity 

 which they bring with them from the Atlantic. This state of 

 things is occasionally varied by the centre of the storm passing 

 in its easterly course across England, along the Channel, or over 

 a track even still further south, resulting in easterly and northerly 

 winds at places situated to the north of the centre track, with 

 the probable accompaniments of sleet, snow, or hail, low tem- 

 peratures, chill drizzling rains, and heavy seas. Since, how- 

 ever, the storm-centres usually soon pass on to eastward, the 

 easterly winds accompanying them are generally not of long 

 continuance. But during these past six weeks, notably from 

 December l to 7, 16 to 24, and 31 to January 7, the cyclonic 

 centres have had their course in the south, or to the south, of 

 the British Islands, and consequently easterly and northerly 

 winds have prevailed, particularly in the north of Great Britain. 

 The cyclonic centres, instead of advancing, as ordinarily happens, 

 to eastward, oscillated backwards and forwards — to eastward 

 and then to westward, to north-westward, and then to south- 

 eastward — being thus continually for days together in the south 

 of the British Islands, and hence the persistency of the easterly 

 winds for several days in succession in the north. Finally, since 

 steep gradients prevailed frequently and for considerable periods 

 from North Britain to Norway, the easterly winds acquired a 

 violence, as well as a persistency, almost unprecedented, strewing 

 the coasts with wrecks, and raising high tempestuous seas, 

 which, particularly when conjoined with the high tides in the 

 beginning of January, damaged harbours and other property to 

 an extent fortunately of rare occurrence in these islands. As 

 frequently happens, gradients were also steep and winds violent 

 over the Channel and the south of England. The snow and 

 rainfalls were also excessive, and blocking up of railways and 

 river floodings, with the inconveniences and disasters attending 

 them, were experienced in all parts except the north-west of 

 Great Britain. At many places the rainfall of December was 

 the heaviest ever recorded. The intimate bearing of the weather 

 of Scandinavia and Lapland on that of Great Britain, and its 

 great scientific importance in forecasting British weather — a 

 pomt we have on various occasions insisted on in this journal — 

 were several times conspicuously illustrated during the singular 

 weather of these six weeks. 



Physics of the Atlantic Ocean. — Dr. Buys Ballot has 

 made a valuable contribution to the physics of the Atlantic 

 Ocean in a paper just published on its mean monthly atmo- 

 spheric pressure. The author v/isely groups the observations for 

 each degree of latitude along the outward and homeward bound 

 routes of the Dutch ships on board which the observations were 

 made. The extent and laboriousness of the work will be under- 

 stood from the fact that for the North Atlantic alone, 175,003 

 observations have been discussed for the outward, and 163,418 

 for the homeward bound route. We shall take an early oppor- 

 tunity of reverting to the subject of this paper ; in the meantime 

 we content ourselves with heartily recommending the paper 

 more particularly to seamen, from its great utility in navigation, 

 seeing that it gives them the average barometric pressure each 

 month for each degree along this great highway of commerce, 

 which, when intelligently interpreted by the wind which happens 

 to prevail at the time, puts them in possession of information, 

 the importance of which it is impossible to over-estimate. 



Weather Maps of Germany. — The Weather Maps of the 

 Deutsche Seeivarte, in the numbers for January, already received, give 

 on a large scale the barometric curve and the hourly direction and 

 force of the wind for the twenty-four hours previous, as recorded 

 by the self- registering instruments at Hamburg. The value of such 

 data in the study of the daily changes of the weather it is un- 

 necessary to point out. This Office has also begun to publish 

 monthly resumes of the weather of the Continent, of which those 

 for January and February, 1876, have appeared, containing 

 short papers by various well-known meteorologists, referring to 

 the weather of the month ; and the averages and extremes for 

 the month are briefly but lucidly discussed for all the stations in 

 Germany, and for many other stations in the countries adjoining. 

 A valuable chart is given showing the tracks from day to day of 

 all the European storms of the month. 



Thunderstorms in Central Europe. — It was recently 

 shown by M. von Bezold that there is a double maximum 

 in the frequency of summer thunderstorms in particular re- 

 gions of central Europe. The results of further researches 

 by others seem to point in many cases to a similar be- 

 haviour in hydrometeors generally. Thus a double periodicity 

 in hailfall has been demonstrated by M. Prettner for Kiirnthen 

 and M. Fournet for the Rhone Valley. And more recently 

 still {Fogg. Ann.), Dr. Hellman, having studied the rainfall 

 in North Germany, is led to the following conclusions : — i. 

 There is a double maximum in both the frequency and quantity 

 of rain in the summer months in North Germany. 2. The 

 first maximum falls, in the case of quantity of rain, in the begin- 

 ning of the second half of June ; that for frequency of rain in the 

 beginning of June ; the second maximum for both cases in the 

 middle of August. 3. The first maximum is more intense in 

 the case of frequency of rain, and weaker in the case of quar .lly. 

 Dr. Hellmann offers an explanation of these phenomena^ for 

 which, however, we must refer to the original. 



Sunspots and Weather. — Prof. Fritz, of Zurich, has shown 

 from a comparison of annual meteorological statistics, that the 

 years distinguished by a maximum of solar spots coincide very 

 closely with those years marked by exceptionally severe hail- 

 storms, and an unusual average height of the great rivers. This 

 law is shown to be in accordance with observations made during 

 the past century in all latitudes, the special periods occurring at 

 intervals of eleven years. 



BIOLOGICAL NOTES 



Chemical Changes Observed during Progress of the 

 Potato Disease. — The Rev. J. H. Jellett details the results ot 

 a series of experiments made to ascertain (i) whether there be 

 any development of sugar during the progresss of the disease, 

 and if so of what kind ? (2) whether there be any perceptible 

 change in the quantity of nitrogen ? It would appear that the 

 first stage of the disease in the tuber is marked by an increase in 

 the quantity of the nitrogen, which seems to attain its greatest 

 value before the stage of discoloration of the tuber. The same 

 stage of the disease is also marked by the development of sugar, 

 both glucose and sucrose. In the second stage of the disease, 

 marked by a great increase in the discoloured part of the tuber, 

 the part which remains apparently sound shows no increase of 

 nitrogen, but a very considerable increase in the quantity of 

 sugar, while in the discoloured part there is a diminution 

 both in the percentage of nitrogen and of sugar. It will 

 be remarked that the development of the sugar contm'ip- 

 for a considerable time after the nitrogen has .-aalned its 

 maximum value. Mr. Jellett has no doubt that the whole of 

 this sugar is formed by the conversion of the potato starch, 

 though he is not aware that there is any known inethod by whicli 

 starch can be made to pass into sucrose ; possibly this effect may 



