Part III. —Eh , < nili A unn<<l Report 



the prevailing south-westerly wind than the eastern side. The winter 

 observations showed that the temperature was somewhat lower off Fairlie 

 than in Rothesay Bay at the same time. There was less difference 

 between the two in summer. Tiie days on which both forenoon and 

 afternoon observations were made showed practically no change of 

 temperature due to sun-heating. 



Off Greenock. — The depth of the anchorage was from 7 to 15 fathoms 

 and the position in the estuary of the Clyde, where the deep water of the 

 Dunoon Basin has shallowed at its meeting with the river. The position 

 of Greenock in the estuary of the Clyde corresponds physically with that 

 of Oxcar at the end of the estuary of the Forth. A considerable range of 

 temperature between surface and bottom was found on almost every 

 occasion ; the fresher river water tending to resist the mixture which 

 rapidly equalises the temperature of water of uniform salinity when 

 exposed to tide and wind. The range between morning and afternoon 

 was also greater than at other Stations, an effect probably due to the same 

 cause. The highest temperature observed was 13 o- 0 on 30th September 

 1890, which was the only September represented in the record. No 

 observations were taken at this place from June to September inclusive, 

 so that the record is practically one of the winter months alone. The 

 lowest temperature noted was 5°*4 on 1st March 1890, at the surface, 

 the reading at 5 fathoms, being 6° '5, and at the. bottom (9 fathoms) 

 6° "8, a typical distribution for early spring. 



Oban Bay. — There are a few summer observations from Oban Bay, 

 from 27th June to 12th July 1887, and 5th June to 28th, 1889. The 

 depths ranged from 11 to 20 fathoms. In June to July 1887, the whole 

 mass of water was practically at the same temperature, showing a gradual 

 warming from IV "2 to 12° - 3. In June 1889, on the other hand, the 

 surface varied from 9° "8 to 13°*7, while the deeper water warmed up 

 uniformly from 9 o- 0 to 11 0, 3, showing a gradually increasing vertical 

 range. 



Castle Bay, Barra, and Vatersay Bay. — These are characteristic Sta- 

 tions of the Outer Hebrides, showing the effect of the North Atlantic water 

 on first leaching land. The anchorages, unfortunately, were rather shallow, 

 averaging about 7 fathoms, but probably pretty free from local disturb- 

 ance. In June 1887 the temperature averaged about quarter of a degree 

 higher throughout its whole depth than that at Oban 'Bay at a later date 

 in the same month. The record takes account of the greater part of 

 June in 1887, 1888, and 1891, the means for the 9 a.m. observations 

 being respectively 11 0, 8, 12 o, 0, and 11 0, 2, 1891 being distinctly colder than 

 the other Junes. The latter part of May 1889 had the mean temperature 

 10 o, 0, and the same period of 1891 was 9 0, 2. These temperatures are, in 

 all cases, higher than those prevailing at the same time in the sheltered 

 water of the Clyde Sea Area. 



Stornoway Loch (Lewis). — This harbour is useful as an indication of 

 the condition of the water in the Minch. The depth at the anchorage was 

 from 6 to 10 fathoms. Observations were made in June, November, and 

 December 1887, January, April, May, June, nid July 1888, May and 

 June 1889, April, May, and June 1890, May, June, and July 1891, and 

 May, June, and July 1892. There are thus sufficient data for the early 

 summer conditions of the various years being compared with confidence. 

 The mean monthly temperatures for 1890, 1891, 1892, as compared in the 

 accompanying Table, shows that Stornoway Harbour was practically at all 

 times colder by about l o, 0 than the water at the Stations in the Clyde Sea 

 Area, and always warmer by about l o, 0 than the water at the Bell Hock 

 on the East Coast. Stornoway was colder than the Firth of Forth at 

 Oxcar, except in April and May 1890, and in May 1891. 



