On the Surface Temperature of North Sea and North Atlantic. 35 



continuous isotherms of our temperature charts, as we have through- 

 out drawn them by interpolation across the land from sea to' sea ; 

 accordingly, this isopleth diagram of ours merely shows us in a 

 diagrammatic way the conditions which exist in the adjacent waters, 

 and those which would approximately exist along this particular 

 meridian, if it were all converted into a water surface with as little 

 change as possible in the distribution of the neighbouring land. 

 We see here again, as in the former diagram, that low minima disturb 

 the simple symmetry of the diagram, and that these are especially 

 perceptible in the neighbourhood of the Scottish coast. 



NDJ FMAMJJyA SONDJ F 



Fig. 29. — The same for longitude 0° 



Fig. 29, for the meridian of 0°, is again, in the same manner as 

 Fig. 28, an artificial diagram ; for this meridian crosses the land in the 

 south-eastern and eastern counties of England. The diagram is 

 closely comparable with the former ones, showing the same disturb- 

 ance in regard to the minimal temperatures. 



In 5° E. (Fig. 30), if we compare our diagram, for instance, with 

 that for 5°'W., various points of contrast will become apparent. Let 

 it suffice here to point out (1) the still greater depression of the 

 minima, (2) the fact that the chief depression appears where the line 

 of the diagram lies nearest to the Norwegian coast, and lastly. 



