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Part III. — Thirteenth Annual Report 



Tho stations have been classified into three groups, northern, central, 

 and southern, and in every group the column on the left is that of a 

 station further up the Forth than that on the right. The maximum tends 

 to diminish as the station is nearer the influence of the North Sea, and the 

 minimum notably increases in the more easterly stations, so that the range 

 near Inchkeith or off Musselburgh is much greater than that off An- 

 struther, the May, or the Bass, or in the open sea, which shows the lowest 

 range of all. 



Perhaps the most interesting fact shown in the table is the great varia- 

 tion of temperatures from year to year. The maximum temperature was 

 exceptionally high in the Forfh, as at all other stations, in 1893, and 

 exceptionally low in 1892 ; in 1891 it was little above the average, in 1890 

 decidedly below, and in 1889 distinctly above the mean. In 1893 the 

 minimum temperature was under the average, but not so much so as in 

 1892, the exceptional lowness of the summer temperature in the latter 

 year, however, making the range of temperature distinctly under the 

 average, while in 1893 the extremes were the greatest yet experienced 

 since the 1 Garland's ' observations began. During the early months of 

 1890 the water was warmer than it has been during the five years of 

 which we have records ; and this made the difference between winter 

 and summer temperatures during that year much lower than usual. The 

 range of temperatures in 1891 is very little above the average, while in 

 1889 both maxima and minima are more extreme than in the mean. 



These years 1889-93 thus present marked differences in temperature 

 conditions, as well as in transparencies. The salinities should be treated 

 in a similar way, and also the biological observations. From a com- 

 parison of these data we should be able to learn something of the relation- 

 ship between the physical conditions of the Forth and the organic life in 

 its waters — and it seems to me that it is highly desirable that the Board 

 should have this inquiry carried out at an early date. 



