138 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 70 



to 31° west longitude, shown in curve VI. Finally we give a similar 

 curve VII for the two Dutch io° squares in the Indian Ocean com- 

 bined. At the bottom of the figure is shown a curve S for the sun spot 

 relative numbers and the curve M for the degree of disturbance 

 of the three magnetic elements in Potsdam (characteristic mean 

 according to Eschenhagen's system). The values of curves S and 

 M are obtained by three years' smoothing and the curves are inverted. 



On the whole these temperatures curves, I to VII, give un- 

 questionable agreement with the sun spot curve though with some 

 irregularities. The curve III and curve II combined show the two 

 sun spot periods between the sun spot maxima in 1883 and 1905. 

 This is the case with the combined curve V and VI. The minima 

 and maxima of these curves do not coincide, however, exactly with 

 the maxima and minima of the sun spots, but come a little later, see 

 for instance the years 1884, 1890 and 1894. Sometimes earlier, as in 

 the years 1904-5, 1909-10, and also the minimum of curve V in the 

 year 1891. The curve III has a depression in the years 1899 to 1901 

 when it was sun spot minimum, while the curves II and I have 

 very well marked maxima in these years. 



The curves we have compared (see figs. 21 and 22) for the 10° 

 longitude fields of the route Channel to New York show a phase 

 displacement of the temperature minimum and also of the maxi- 

 mum, particularly in February, so that the minimum and maximum 

 occur earlier in the western part of the ocean between 50° and 

 60° west longitude, than further east at 20° to 29° west longitude. 

 A similar displacement of the minimum and also of the second 

 maximum is shown by the smoothed I, II, IV, and VI, figure 57. The 

 minimum and maximum are found earlier on the equator (curve 

 VI) than further north (see curves IV, II and I). Such a displace- 

 ment of the minimum and of the maximum is, however, not to be 

 seen on the consecutive twelve-monthly smoothed curves III, IV, 

 VII, and IX of figure 55. 



The Atlantic temperature curves, particularly IV and VI, have 

 also the same character as the curve VII for the Indian Ocean, 

 only that this latter shows very low temperature values in the year 

 1909 and 1910. By comparing the Atlantic curves I, II, IV, and 

 VI with the inverted sun spot curve S, of figure 57, one sees that 

 the temperature minima are one or two years before the sun spot 

 maximum, and the temperature maximum of 1909 and 19 10 was 

 even as much as two or three years before the sun spot minimum. 

 However, as regards the minima, the temperature curves I, II, IV 



