76 



DR HUGH ROBERT MILL ON THE 



the curve is practically unchanged. On the 21st June 1886 (Curve 2) the wind was 

 light from the north, tide half hour ebb ; on the 22nd (Curve 3) squally from the south, 

 and the tide was about half flood. These different conditions seem sufficiently to explain 

 the change. 



Curves 13 and 14 (August 15th and 16th, 1887) are interesting in being, so far as 

 the defective data of Curve 14 can show, precisely alike, with one small exception. This 

 is a break in the uniform paraboloid by 3 fathoms of straight line, just above 20 fathoms 

 in No. 13, just below it in No. 14. Curve 12 is reproduced as one of the most perfect 

 specimens of a positive paraboloid. 



Curves 1 7 and 18, for January 3rd and 7th, ] 888, have almost the same mean tempera- 

 ture (46° and 46°*07). The former is above 46° below 10 fathoms, and below 46° 

 above that depth, while in the latter this relation is inverted. But since the extreme 

 temperatures in No. 17 are 45° # 8 and 46°'2, and those in No. 18 are 46°*4 and 45°*9, 

 there is scarcely room for detailed comparison. 



The homothermic change of the lower layers in this basin, where there is an excep- 

 tionally complete system of interchange of water, strongly confirms the explanation of 

 the modus operandi of this form of change, arrived at from the study of the Arran Basin. 



Observations at Minard and Paddy Rock. — At Minard, Loch Fyne is con- 

 stricted, and the surface divided into several channels by a group of islands. The two 

 chief channels in which observations were sometimes made are "Minard" on the 

 western shore, with a maximum depth on the sill of 12 fathoms, and " Paddy Eock " on 

 the eastern shore, which is somewhat wider, and has a maximum depth of 18 fathoms. 

 These channels separate the deep Upper Basin of Loch Fyne from the Gortans Basin. 



The density of water may be assumed as the mean of that at Gortans and Furnace. 



Table XXVI. — Temperature Observations at Minard and Paddy Bock. 



No. ... 

 Date . . . 

 No. of Points 

 Temp. . . . 

 Slope . . . 

 Placet • • 



1 



2 



2(a) 



3 



4 



5 



6 



7 



8 



9* 



10 



5.2.87 



29.3.87 



29.3.87 



10.5.87 



15.6.87 



7.7.87 



15.8.87 



23.9.87 



6.1.88 



6.1.88 



16.10.88 



3 



6 



6 



4 



4 



6 



8 



3 



6 



9 



4 



44-3 



44-1 



44-2 



45-5 



49-6 



51-8 



52-2 



52-9 



46-4 



46-5 



49-9 



-0-8 



+ 0-4 



+ 0-2 



+ 0-6 



+ 2-3 



+ 5-7 



+ 3-0 



+ 0-8 



-0-1 



+ 0-4 



00 



M 



P 



M 



M 



P 



P 



P 



P 



P 



M-P 



P 



* Deep water. 



t M = Minard Channel. P = Paddy Rock Channel. 



These curves show no notable peculiarities, except that the change of temperature 

 is mainly confined to the superficial 5 fathoms. The great range of No. 5 is remarkable : 

 surface temperature 60°'4, at 4 fathoms 50 o, 6, and at bottom (15 fathoms) 49°*2. 



Observations at Furnace. — The position where observations were made is defined 



