262 



BATHYMETRICAL SURVF.Y OF 



far to the north on the flanks of Beinn Dearg (3547 feet). Still further 

 on the river Conon is joined by the river Orrin, and finally falls into 

 the head of the Cromarty firth at Dingwall. The river Glass, which 

 in its course flows through Loch Glass, rises on the flanks of Beinn nan 

 Eun, and empties itself in the Cromarty firth at Balconie Point. The 

 river Alness, which flows through Loch Morie, rises on the flanks of 

 Beinn a' Chaisteil, and falls into the Cromarty firth at Alness Point. 

 The geology of the district is dealt with by Drs. Peach and Home, 

 whose notes are appended, as well as a few biological notes by Mr. James 



O I 2 3 4 5 



' English Miles 



FIG. 44. INDEX MAP OF THE CONON BASIN. 



Murray. Mr. R. M. Clark, B.SC., who took part in the survey of the 

 lochs in the Conon basin in 1902, has supplied us with several series 

 of temperatures taken by him the previous summer (1901) in Lochs 

 Achilty, Garve, Achanalt, a' Chuilinn, and a' Chroisg, which are here 

 incorporated.* 



* These temperature observations, taken by Mr. Clark in the summer of 1901, are 

 interesting, as compared with the observations taken in the same lochs in the summer 

 of 1902, when viewed in connection with the atmospheric conditions in the two seasons. 

 It will be observed that all the readings taken in the superficial waters of these lochs 

 in 1901 are higher than those taken in 1902, and this is evidently related to the warmer 

 season in the first-named year. Thus the mean temperature over Scotland for July, 



1901, was 61-8 Fahr., or 3 above the long-period average for that month, while for July, 



1902, it was 54-4, or 4 below the average ; for August, 1901, tie mean was 57 0< 5, or 

 1 above the average, while for August, 1902, the mean was 53 '9, or 2^ below the average. 

 The nearest station to the Couon basin lochs from which observations are available is 

 Inverness, and the mean temperature there for July, 1901, was 61-0, or 4 above the long- 

 period average, while for July, 1902, the mean temperature was 45-4, or 3 below the 



