11(1 



DR HUGH ROBERT MILL ON THE 



The average density at the head was greater than that at Shandon, but the extremes 



Mere also greater. 



Table XLII. — Temperatwre Observations at Garelochhead. 



No 



1 



2 



3 



4 



5 



6 



7 



8 



9 



10 



Date 



13.4.86 



21.4.86 



16.6.86 



3.8.86 



24.9.86 



11.11.86 



28.12.86 



2.2.87 



25.3.87 



6.5.87 



No. of Points 



4 



7 



4 



4 



4 



3 



6 



3 



3 



5 



Temperature 



41 -6 



4-1-0 



47-9 



53 T 



53-9 



50-1 



43-8 



42-9 



43-0 



46-4 



Slope 



+ 1-1 



+ 1-8 



+ 0-6 



+ 04 



-0-2 



-0-7 



-1-8 



-0-7 



-0-1 



+ L8 



No 



11 



12 



13 



14 



15 



16 



17 



18 



19 





Late 



13.6.87 



6.8.87 



30.9.87 



29.11.87 



9.2.88 



28.3.88 



7.6.88 



20.8.88 



6.9.88 





No. of Points 



3 



6 



4 



3 



3 



3 



3 



3 



3 





Temperature 



51-0 



58-5 



54-4 



44-9 



43-6 



41-7 



47-7 



55-7 



54-8 





Slope 



+ 0-7 



+ 1-2 



-01 



-1-7 



o-o 



o-o 



+ 0-9 



+ 2-4 



+ 0-5 





The mean of these curves gives 48°"3 as the average temperature of the station, which 

 is a little higher than any other average temperature in the loch; the range from 41° *6 

 in April 188G (41°7 in March 1888) to 58°'5 in August 1887 is also the largest found. 

 On account of the slight depth comparatively little interest attaches to the form of the 

 individual curves, which were only delineated satisfactorily in a few cases. So far as the 

 depth admitted, the forms of paraboloid and S-shaped curves, and the changes of slope, 

 were shown as at Shandon. No. 12 is an interesting case of a paraboloid curve formed 

 perfectly from 2 fathoms downwards, but turned up abruptly to the surface where the 

 temperature was 3° lower than the rest of the curve would lead one to expect. The 

 correctness of surface temperatures, as a rule, is open to doubt. In curve 10, for instance, 

 a surface reading, when the observations began, gave 52°. and when they were over, only 

 50°5. A further fall of 0°'9 would have given the same form of curve as in No. 12. 



No. 10 was made at lG h 40 on May 6th, 1887, No. 12 on August 6th, 1887, at 13 h 45 in 

 rain. 



The three maxima embraced by the observation show Garelochhead to have the 



highest temperature, and Row I. the lowest, Row II. and Shandon lying close together. 



At the three minima the Garelochhead curve is almost the same as the others, but it 



Bhowa a tendency to rise and fall more rapidly, thus having a slightly longer warm 



and cold season, and slightly shorter transition seasons than the other stations. 



It is interesting to observe that the difference in mean temperature of the vertical section 



between the different stations is greatest at the Autumnal maximum, and least (practically 



imperceptible) at the Spring minimum. 



